I come from a very devout Catholic family, and when I was growing up we went to Mass every day—not just on Sundays. When I was very small Mass was just boring. I fidgeted, day-dreamed, tied the ribbons of the hymnals together, teased my sister, and generally made a nuisance of myself. But then, when I was about 13, I started to serve as an altar boy. The priest whom I served was named Don Reto. He was chaplain at the theological college where my parents taught (both of my parents are Catholic theology professors). Don Reto is one of the best people I have ever met. He changed my life. When he celebrated Mass, it was clear that he believed in it with every fiber of his being. He was full of awe and reverence, a holy fear. Watching him I began to see why we call the Mass “the Sacred Mysteries” and “the Holy Sacrifice.” Not that I could have explained what those words meant at the time. But it was clear to me that Don Reto had found something in the Mass to which it was worth devoting his whole life.

Don Reto’s “holy fear” of what he did in offering Mass made him completely fearless about other things. The latest chapter of the unending scandal of sexual abuse in the Church has once more revealed how much corruption there is among priests and bishops. Don Reto was one of the few who was utterly fearless in denouncing such corruption. He had an Old Testament prophet’s hatred for people who used the Church as a façade for their own selfish ends. He was eventually dismissed from the theological college for what was called a “habit of suspicion” towards Church authorities. Sadly, subsequent events have only confirmed his suspicions.

Since my ordination as a Catholic priest in 2011, I have celebrated Mass 2,803 times— unless I have made some mistake in the little book in which I record each celebration. The celebration of Mass is the main reason why Catholic priests exist, and so people often ask me: what is it like to celebrate Mass?

Basically, there are two different ways of experiencing it. Sometimes when I celebrate Mass I am full of what Saint Ignatius of Loyola called “spiritual consolation.” This was the case at my very first Mass. The first time I went up to the altar I was fully present in the moment, full of love for God and certainty of his presence. I had a great sense of my own unworthiness, but with a paradoxically joyful sorrow at that unworthiness. I said the following words: On the day before he was to suffer, he took bread in his holy and venerable hands, and with eyes raised to heaven to you, O God, his almighty Father, giving you thanks, he said the blessing, broke the bread and gave it to his disciples, saying: Take this, all of you, and eat of it, for this is my Body, which will be given up for you. And my entire being seemed to be absorbed in them. I have experienced something similar on many subsequent occasions.

But the second way of experiencing the celebration of Mass is in what Ignatius calls “spiritual desolation.” For me desolation is experienced as distraction— as being unable to be fully in the present moment, having my thoughts flee into memories of the past or fantasies about the future. This happens particularly when my heart is disturbed by what Ignatius calls “the unquiet of different agitations and temptations”— that is, when uncontrolled feelings of anger, resentment, anxiety, fear, lust, shame (or whatever) prevent the mind from coming to rest on what I am doing. On such occasions I say: On the day before he was to suffer, he took bread in his holy and venerable hands… but my mind is saying, ‘why was Brother So-and-So such a jerk to me yesterday?’

That second experience—the experience of desolation and distraction—is discouraging, but it is also important. The Catholic tradition puts a lot of emphasis on interpreting desolation as a sign of the need for spiritual and moral growth. Growth, particularly, in the good habits or virtues, which bring one’s feelings under the guidance and control of the spirit, so that one will be more able to be present in the moment.

Of course, all of this has to do with the basic Christian interpretation of human life: that we human beings have received our whole being and world from a source— we are “created.” God is not one more thing among the many things in the universe, but rather the sustaining cause of everything. He is like the author of play in which we are characters, or a cellist playing a piece of music in which we are notes. But He is not only the source, He is also the goal of our lives.

But, on this account, human beings have been in some way separated or estranged from the source and goal of their being. This is what is known as “original sin.” This estrangement from God causes a deep-level pain, a kind of unbearable loneliness at the center of the soul. And much of human life consists in chasing after distractions to prevent ourselves from feeling that loneliness. We seek after excitement, pleasure, fame, power, wealth, etc. And these distractions quickly become destructive addictions, destructive of the self and therefore wounding to others. What our hearts truly desire is to give ourselves to our source and goal, but we think that we can satisfy ourselves by taking other things.

The paradox is that all things are made by God, and desired rightly could lead us to Him, but instead they lead us away. To quote Augustine again: “You were within me God, but I was outside of myself, in the external world, and sought You there, and in my unlovely state I plunged into those lovely created things which You made. You were with me, and I was not with You.”

The solution to this estrangement from God is that the author enters the play, the cellist becomes one of the notes being played. God Himself enters the world and becomes a human being: Jesus of Nazareth. And as a human being He does what all human beings desire to do in the depths of their hearts, but are unable to do because of sin: He offers a sacrifice. That is, He gives Himself entirely back to God. A sacrifice is a gift. And the desire of our hearts is to give ourselves as a gift to God. Jesus enacts this sacrifice on the cross by willingly suffering death. He does the opposite of the flight into distraction: instead of preferring lesser things to God, He is willing to give His very life for God. And thereby He “atones” for all the ways in which we have turned away.

In ancient sacrifices, a sacrificial animal was offered in place of the people. By destroying the animal, they were giving a sign of their willingness to give themselves to the deity. After the sacrifice, the sacrificial animal was often eaten in order to show the identity of the people with their sign. According to Catholic teaching, whenever the Mass is celebrated Jesus’s body and blood become really, truly, and substantially present in the guise of bread and wine. His sacrifice on the cross is thus made present, and we are united to it. In eating His body, we unite ourselves to His sacrifice and are thus able to give ourselves (together with Him) to God. Thus, our estrangement from God begins to be overcome.

But the experience of desolation and distraction shows us that this union takes time and repetition to transform our lives. Our habits still make us live “outside.” God is with us, but we are not always with Him. The experience of desolation makes me want to transform my life—to heal my bad habits, and atone for the evil I have done to others. “I appeal to you by God’s mercies,” Saint Paul says, “to offer up your bodies as a living sacrifice, consecrated to God… there must be an inward change, a remaking of your minds.” What is it like to celebrate the Mass? It is like reminding oneself of that again and again and being filled with a desire for that transformation.

To try to celebrate Mass with one’s whole heart is also to be filled with a desire to combat corruption in the Church. As a Catholic priest, the abuse scandal in the Church is given an extra edge of horror to me by the fact that the abusers were priests, supposed to have consecrated their lives to the Holy Sacrifice. What they did instead was the exact opposite. Instead of “this is my body offered up for you,” they essentially said, “this is your body, which I am going to take.” That fills me with anger. It makes me angry to think of altar boys who found in priests not an inspiring example of sacrificial dedication (as I did), but instead horrible betrayal and abuse. And it makes me angry that bishops and popes were not angrier when they heard about these abuses. These are men who celebrate the Mass every day. How could they fail to boil over with righteous anger at these evil priests who perverted their priesthood into its opposite? When Pope Saint Pius V heard of similar crimes 450 years ago, he not only ordered the priests who committed them to be exposed and stripped of all their ecclesiastical privileges, he had them turned over to the secular authorities to be put to death. The Church today needs a similar zeal, so that she might be to all what she has ever been to me: a conduit of grace and consolation.