I want to address the wager between hospitality and hostility. When faced with the stranger, do we open or close the door? Do we reach for a weapon or extend an open hand? This is one of the inaugural dramas of human ethics.

Hosting the stranger is not just some abstract virtue, however, but a living existential struggle - a struggle with crucial contemporary implications. The ethos of hospitality is never guaranteed; it is always shadowed by the twin of hostility. In this sense, hosting others - aliens and foreigners - is an on-going task, never a fait accompli.

Two models of hospitality

Let me begin with the contemporary debate that is going on in philosophy regarding two different approaches to hospitality.

The first is the "deconstructive" approach. This sees true hospitality as absolute and is represented by Jacques Derrida and other deconstructionist thinkers in Europe and the United States. The basic idea here is that pure hospitality is unconditional, for if you truly welcome a stranger you don't ask where he/she has come from or for what purpose. You don't ask the stranger for ID or passports. Pure hospitality, this account goes, is not about a contract or an exchange - it's about a radical exposure to the other. A welcome without why.

When there is a knock on the door, you don't know whether the person is a monster or a messiah. That's the level of risk that real hospitality involves. As soon as you put it into laws, rules, norms and pacts you are removing the challenge, taking the trust and daring out of it. Here is what Derrida says in his book Of Hospitality:

"Let us say yes to who or what turns up before any determination or anticipation, whether or not it is to do with a foreigner, an immigrant, an uninvited guest, an unexpected visitor. Whether or not this new arrival, visitor, is the citizen of another country, human, animal or divine, a living or dead thing, male or female."

In short, absolute hospitality is a "yes" to the stranger that goes beyond the limits of laws, rules and conventions which require some check on who to include and exclude. It defies border controls.

By putting it in such a hyperbolic way, Derrida is asking us to make a leap of faith in the stranger as unknowable and unpredictable Other. He acknowledges that such hospitality is impossible; but he suggests we should strive for it anyway.

A second understanding of hospitality is characterised by the "hermeneutic" approach. This takes its cue from Paul Ricoeur, who argues for a certain prudent discernment between different kinds of strangers. Here we are dealing with conditional rather than unconditional hospitality, with what is possible rather than impossible.

Ricoeur bases this hermeneutic approach on the model of a "linguistic hospitality" that you enact, for example, when you translate a guest language into a host language. The host language welcomes its guest and, of course, in the act of translation the host is transfigured by the guest language and vice versa. Antoin Berman refers to translation accordingly as l'epreuve de l'etranger - the test or trial of the foreign - because we can never have a perfect translation that totally assimilates or accommodates the stranger's language.

In translation the host and the guest are both transformed, and may in fact be reversed in their roles. That is to say, because there is no total or adequate translation there is always a remainder, an untranslatable kernel, which we are forever seeking to translate into better terms.

This ineradicable difference between languages calls in turn for a creative congress of ideas, sentiments, convictions and life-views. And it is very often this very dialogical tension between the translatable and untranslatable which represent what is best in our cultural histories.

Take the classic example of the translation of the Hebrew Bible into Greek. This involved a productive exchange between two very different notions of being. From the Septuagint the specifically Hebrew notion of being as becoming - as in the phrase "I am who shall be" (Exodus 3:15) - challenges the whole Greek notion of being as self-identity. The point here is that in this famous translation the host language (Greek) has to open up its notions of ontos on or einai to accommodate the guest language (Hebrew) with its idea of divine being as personal revelation, promise or epiphany.

Likewise, the Hebrew guest has to accommodate to the Greek host. So in one sense, Biblical language acts like a Trojan horse, upsetting and sabotaging the Greek metaphysical notion of being; but in another sense, it is also learning to prepare itself for immersion in a strange culture - a Hellenic worldview which is also creatively transformed by the challenge of the new. Out of that shock of encounter, of mutual translation if you will, the host and the guest emerge as an event of interlinguistic hospitality.

However, the hospitality of translation is not unconditional, arbitary or absolute. If the foreigner knocks on your door, you have a right to say, "If I invite you into my host language, are we both going to benefit or are you going to destroy me?" (Or to take a more dramatic analogy, if you're in the Warsaw Ghetto and you are protecting your Jewish family and the SS knock and ask, "Can I come in?" do you say "Yes" or do you say "No"?)

The ethical conditions of hospitality require that sometimes you have to say "no." We are often obliged to discern and discriminate; and, so doing, one generally has to invoke certain criteria to determine whether the person coming into your home is going to destroy your family or is going to enter your home in a way that, where possible, is mutually enhancing. You do not know for sure, of course, what the outcome will be. It is always a risk. To cite Derrida, the stranger who arrives into your home could be a psychopath or a messiah.

Linguistic hospitality is not indiscriminate. It has a right to maintain a certain fundamental difference between languages, thereby resisting the temptation to reduce host and guest tongues to a single identity of meaning. Good translation seeks to avoid fusion or confusion - the error of reducing the other to the same, the stranger to the familiar. On the contrary, genuine linguistic hospitality can only occur where the unique singularity of each stranger and each host, each author and each reader, is respected.

Guest and/or enemy?

Bearing these two models of unconditional and conditional hospitality in mind, I want to offer a brief account of two traditions in Western culture that have informed our contemporary undertanding of hospitality. The first is the Indo-European: the second is the Abrahamic.

The Indo-European tradition has been well analysed by Emile Benveniste in his classic work Indo-European Language and Society. Here he looks at the double meaning of the root of hospitality - hostis meaning both guest and enemy. Originally, hostis carried the meaning of guest and only gradually took on the meaning of enemy. Benveniste asks why.

He claims that originally the notion of hostis involved someone in an equal, reciprocal relationship demanding trust, a laying down of a one's weapons, a conversion of hostility into hospitality. It was only later when interpersonal or intercommunal relations of trust were replaced by abstract relations between impersonal states that hostis assumed the connotations of enemy. Henceforth, hospitality was intrinsically linked to the possibility of hostility and so became a drama of choice and decision. Benveniste writes of this transition of the meanings of hostis thus:

"The primitive notion conveyed by hostis is of one who repays my gift with a counter gift, thus like its gothic counterpoint gast, the Latin hostis at one period denoted the guest. The classical meaning enemy must have been developed later when reciprocal relations between clans were succeeded by exclusive relations of civitas to civitas."

In other words, once communities evolved into large sovereign states, the intimate relations between people, which were the basis of hostis as guest, were transformed into a suspicion of the hostis as a potential threat. Why? Because at that stage the abstraction of state sovereignty had rescinded from personal relationships as the basis of early community life.

The other main term at the root of hospitality is hospes, and here also Benveniste notes a basic ambivalence. He makes the point that the terms hospes and hospites contain the root word pet, potestas - power. So the host served as a sort of guest-master who had the capacity and the power to welcome or refuse foreigners into his home. In other words, the guest-master had the power as master of the house and identity to include or exclude who he wishes.

And so we witness within the evolution of Indo-European societies the notion of both a favourable stranger developing into the guest and a hostile stranger developing into the enemy. The wager of hospitality then becomes a wager of "hostipitality." This term is a coinage of Derrida's - we can't talk about hospitality without the possibility of hostility and vica versa. One can turn into the other or back again. Hospitality is never a given; it is always a challenge and a choice.

In sum, hostis is a double term at the root of both hospitality and hostility. The positive sense of host relates to one who receives the guest as an Other (stranger or foreigner) in a reciprocal gesture. But this positive sense is gradually overcome in the development of anonymous states and regimes.

In historical times, as Benveniste points out, the custom had lost its force in the Roman world for it presupposed a type of intimate relationship that was no longer compatible with the established regime. When an ancient community becomes a nation-state the relations between man and man or clan and clan are abolished. All that persists is the distinction between what is inside and what is outside the civitas. The word hostis thus assumes a hostile flavour and henceforth it is applied only to the enemy.

Hospitality-turned-hostile

The distinction between inside and outside can be seen in the development of modern notions of sovereign identity, but it goes back to much older oppositions between Greeks and Barbarians, Romans and Etruscans.

Hence, the two original terms for nation - nation and gens - came from the claim that to be citizens of a sovereign nation-state was to be defined over and against those who did not possess the natural birthright (natus and genitus) of the legitimate State. This political strategy of inclusion/exclusion finds more egregious expression in contemporary forms of exclusivist divisions between Aryan or non-Aryan, Serb or Bosnia, Jew or Palestinian and so on.

With the emergence of the notion of absolute sovereignty - which is "one and indivisible," according to Rousseau - there is already a danger. What happens to those who are not part of the "one and indivisible" state - the alien, outsider, emigrant, non-resident, non-confirmist? What happens to those who represent a minority - religious, ethnic, linguistic, cultural? Does the State isolate them or send them home? If they are within the nation, do they exist if they are not part of the nation? For Hitler, the Jewish, Gypsy and other non-Aryan communities did not belong and so lost their right to "exist."

This is the danger of others becoming aliens, and strangers becoming scapegoats. But against such exclusivist tribalisms, one witnesses important counter examples. We already find such counter examples in the Homeric Greek code of philoxenai, epitomised in the fact that Zeus was the protector of strangers. This ethic of sacred hospitality was continued into Plato's philosophy where Socrates is celebrated as a truth-telling Stranger who in turn welcomes the Eleatic stranger in Parmenides, one of the foundational texts in Western culture.

And yet in Graeco-Roman societies - as in our modern societies - there are many narratives of strangers, guests and enemies who come into the home and destroy it. One of the most ancient instances of hospitality-turned-hostile is the story of the Trojan Horse, where the Trojans open their gates to the gift of their adversaries only the find their hospitality betrayed. This raises again the critical question of conditional or unconditional welcome to the stranger: were the Trojans right to make that act of trust not knowing whether it would go wrong, or should they have been more suspicious of their Greek counterparts?

An ethic of absolute hospitality requires us to take the risk without asking for identity papers or guarantees of good behaviour. Each person faced with a stranger at the door is faced with this age-old dilemma of conditional and unconditional welcome.

Hospitality and cruelty in the desert

Let me now move to the second tradition of hospitality - the Abrahamic. In the first Biblical narrative of hospitality, we find Abraham and Sarah welcoming three strangers in the desert. The strangers appear out of nowhere and the hosts accept them without asking if they be friend or foe. This is how the story goes.

It is a hot dry day in the desert and Abraham is sitting under the shade of an oak tree. His wife Sarah is inside the family tent sheltering from the midday sun. She is not happy; she is over one hundred years and she is barren. Her servant woman Hagar is younger and more attractive than she and more fertile.

Abraham is brooding about his unhappy wife and the future of Israel, when suddenly a shadow flits across the sunlit ground in front of him. He looks up to see three foreigners standing before him and he is filled with fear. Why have they come, he wonders - perhaps to kill him and his family? There are, after all, three of them and he has two women to protect - his wife and his servant girl. Should he kill the strangers?

But instead of reaching for a weapon or retreating into his tent, Abraham finds himself running towards the visitors. He greets them, bows to the ground and invites them to a meal. He asks Sarah to knead three measures of the best flour to make loaves while he catches a calf and prepares it with curds and milk. Then Abraham stands under the oak tree and watches his guests eat.

When they have finished the strangers announce that when they will return in a year Sarah will be with child. The barren Sarah, standing inside the entrance to the tent laughs when she hears this for it is quite impossible for her to be with child. But the visitors repeat the promise - nothing is impossible to God. The child will be called Isaac, which in Hebrew means "laughter," because the impossible becomes possible.

The strangers are thus revealed to be divine. Just as Zeus appears to Philomen in the guise of a stranger, Yahweh appears to Abraham in the guise of three strangers who invite Abraham and Sarah to an ethic of absolute hospitality.

In the biblical tradition, Abraham is recognised as the wanderer par excellence, the tent dweller, celebrated in Psalm 119: "I am a stranger on this earth, I am a wandering Aramean." To this day, the Jewish festival of Sukkut is a time when Jews erect a tent to remind themselves that they are descended from a nomad who showed hospitality to strangers.

But this does not mean that hospitality always wins the day. The shadow of hostility is never far off. Hence, in the Genesis narrative of hosting strangers, Abraham turns into a very immoral despot. He banishes Hagar into the desert with her son Ishmael where they would have died if it were not for Yahweh intervening. So the great founding patriarch, who is capable of the greatest act of hospitality is also capable of the greatest cruelty when it comes to the exclusion of his second "slave" woman.

The same goes for the Abraham we meet on Mount Moriah with his son Isaac. He hears two voices. One says "Kill your son," in keeping with the ancient ritual practices of human sacrifice to the Gods. But another voice says, "Do not kill your son, welcome him as a gift from God, not as a mere possession to dispense with as you will (including blood sacrifice), but receive Isaac back as a stranger, as a gift."

This scene is wonderfully dramatised by Kierkegaard in his book Fear and Trembling. The choice between hostility and hospitality is always one taken in fear and trembling because, as Rilke put it, "every angel is terrible" and we don't know if the terror that we recoil from is actually a violence which may destroy us or a shock which may transfigure us.

There is always that difficult and inescapable wager at the cusp between welcome and rejection.

The stranger as the face of God

The entire Bible, it could be said, is made up of struggles between two different ways of responding to the alien. So Saul goes out to bring destruction on the Amalekites, but in the battle against the foreigners decides to abandon blood-lust and commit instead to mercy.

Jacob meanwhile wrestles with a dark anonymous "someone" right through the night; he fights with what he perceives to be a threatening adversary, until he finally opens himself to the Other (Genesis 32:25). Receiving a divine mark upon his hipbone, and the new name of "Israel," Jacob opts for peace, ultimately acknowledging "the face of God" in the visage of his mortal enemy. Indeed, it is significant that the very day after he has wrestled thus with the angel, he is able finally to embrace God in the guise of his estranged rival brother, Esau.

The message seems to be this: the divine, as exile, is in each human other who faces us, defenceless and vulnerable, asking to be received into our midst. The face that serves as trace of transcendent divinity is also a portal to humanity in its flesh-and-blood immanence. Or, as Emmanuel Levinas puts it, "The epiphany of the face qua face opens humanity. The face in its nakedness as a face presents to me the destitution of the poor one and the stranger."

My hospitable relationship with the stranger, in sum, gives meaning to my relations with all strangers, proximate or distant, human or divine. In this sense, it is an option for justice over murder.

Here we might recall one of the most central prayers of Passover (from Exodus 22): "You shall not oppress a stranger, for you know the heart of the stranger, having yourselves been strangers in the land of Egypt." And another Passover text (Sefer Ha-Hinukh 431), explains this Exodus passage as a reminder that

"we have experienced the great suffering that one in a foreign land feels. By remembering the pain that we ourselves have undergone, from which God, in God's mercy, delivered us, our compassion will be stirred up towards every person in this plight."

In support of this reading, we might also recall how three of the earliest books of the Bible are about hosting strangers - Job, Ruth and the Song of Songs. Job challenges Yahweh before finally accepting his strange ways. Ruth is a Moabite alien welcomed by Boas into his home, thereby initiating a long line of hybrid descendants including David and Jesus. And the Song of Songs may be cited as paradigmatic of the coming together of Israel and its Egyptian rival - King Solomon hosts the foreign "Shulammite" woman, defying tradition to embrace this "black and beautiful" stranger as his bride.

Hosting your Other is more divine than protecting your own - which is arguably why the Hebrew Bible has thirty six commands to "love the stranger" and only two to "love your neighbour." In this respect, Deuteronomy is one of the richest books in references to the stranger. Let me cite a few characteristic passages:

"He shows his love for the stranger by giving him food and clothing" (10:18);

"Cursed is he who distorts the justice due a stranger, orphan and widow" (27:19);

"You shall not pervert the justice due a stranger or an orphan, nor take a widow's garment in pledge" (24:17)

"You shall rejoice to the Lord your God ... and the stranger and the orphan and the widow who are in your midst, in the place where the Lord your God chooses to establish His name" (16:11).

There are several telling things about these references to the stranger in our midst.

The stranger is associated with the name of God.

The stranger is invariably linked with allusions to orphans and widows - vulnerable and defenceless ones without family or guarantor.

The advent of the stranger calls for a "justice" that seems to go beyond normal conventions of homeland security, which tend to exclude strangers, orphans and widows. The very fact that the Lord must repeatedly enjoin hospitality to prevent hostility toward the foreign is itself an acknowledgement that initial responses to aliens are more likely to be fear rather than love. So that if Deuteronomy recalls that "Our father was a wandering Aramean" (Deuteronomy 26:5), the same text is also guilty of the most egregious expressions of exclusion towards wanderers beyond the tribe.

The Latin translations of the Hebrew ger (stranger, or foreigner) as advena and peregrines are particularly suggestive in that they connote one who comes from outside, from afar, from the future (advena), and one who migrates across borders of nation, tribe or home (peregrines, as in the English peregrination).

The stranger, in short, is the uninvited one with nowhere to lay its head unless we act as "hosts" and provide a dwelling. There is a sense of radical surprise about the coming of this estranged and estranging outsider - a sense of unknowability calling for risk and adventure on our part.

Hospitality to the irreducibly Other does not come naturally. It requires imagination and trust. So while the Torah acknowledges the predictable impulse to persecute intruders, it exhorts us to overcome our murderous impulses and welcome the advening one: "What is hateful to you do not do to another. This is the whole Torah; all the rest is commentary."

It is noteworthy, I think, that the stranger is often treated as the human persona of the divine. Indeed, what appears as an all-too-human stranger, emerging out of the night to wrestle with us, is only subsequently recognized as divine. The Latin translation of the Hebrew iysh as vir in Latin and anthropos in Greek carries this sense across multiple tongues.

Though some English versions speak here of "angels," most remain faithful to the original biblical sense of the divine revealing itself in and through the human - so, for instance, "Jacob was left alone, and a man wrestled with him until daybreak" (Genesis 32:24). And, we recall again, it is only after the long struggle with the stranger in the dark that Jacob realizes that he has been marked and blessed by the "Face of God." God is revealed apres coup, in the wake of the encounter, in the trace of his passing.

When God is revealed as having been present all the time, God is already gone. That is why God remains a stranger even in the most intimate embrace: "for my thoughts are not your thoughts and my ways are not your ways" (Isaiah 55:8). The Other remains foreign in its most familiar guise. The divine and the human are neither separable nor the same, neither divorceable nor identical.

The inescapable choice

The great stories of the biblical tradition that characterizes the three Abrahamic religions - Jewish, Christian and Islamic - are, I am suggesting, testaments to the paradoxical origins of religion in both violent conflict and peaceful embrace.

This, in effect, makes every dramatic encounter between the human and the divine into a radical hermeneutic wager: compassion or murder. You either welcome or refuse the stranger. Monotheism is the history of this wager. The fact that the Abrahamic legacy has witnessed both traditions of interpretation speaks for itself.

On the one hand, we have ample evidence for those critics who see monotheism as an irremediable source of intolerance and war (from Enlightenment atheists to the likes of Richard Dawkins, Sam Harris and Christopher Hitchens). On the other hand, the Abrahamic legacy provides multiple testimonies to practices of recurrent hospitality - practices which provide powerful resources for those who wish to post-critically retrieve a liberating message in the Bible, one which fosters radical attentiveness to the stranger as portal to the sacred.

In sum, the Abrahamic legacy, along with its Greek Indo-European counterpart, deeply informs our inherited notions of hospitality and hostility. And it is still operative in the theatres of war and peace throughout the world today.

There is no escaping the drama of decision between welcoming or rejecting the stranger outside our borders or in our very midst. The challenge of choice is never over.

Richard Kearney holds the Charles B. Seelig Chair of Philosophy at Boston College and is Visiting Professor at University College Dublin, the University of Paris (Sorbonne) and the University of Nice. His most recent book is Anatheism: Returning to God after God. His is in Australia to deliver the annual Simone Weil Lecture in Human Value at Australian Catholic University.