In his Introduction to Christian Theology lectures at Duke in 1968, Jürgen Moltmann keenly observed that the Church's presentation of the Gospel has shifted from proclamation to personal invitation. Moltmann quotes an American Baptist declaration to demonstrate this shift has had the unintended consequence of diminishing the Christian Gospel to an "introverted and self-centered individualism". In the Bible, the Christian Gospel is "Jesus Christ is Lord of All", and the Apostles proclaimed this good news to the whole world (Phil 2:10-11; 1 Cor 8:6), regardless of whether individuals accepted it or not (Acts 4:25; Rom 14:11). Moltmann explains that the Gospel has been diminished from the Biblical formula, to an invitation asking individuals to "personally accept Jesus Christ as my savior." The Apostles never asked anyone to accept the Gospel (as Karl Barth criticized D. L. Moody), and this diminished formula "I accept Jesus as my savior" appears nowhere in the New Testament. Consequently, the purview of the Gospel has been diminished from its universal scope in reality to a private personal matter benefiting only those who decide to accept it.

Moltmann said, for Christians, faith is self-evident, and unbelief is inexplicable. Faith comes to us, faith is given to us, faith overwhelms us, and we receive faith and believe as a result of it. Our personal faith doesn't come about due to a our personal decision to embrace it (this is a Semi-Pelagian misunderstanding of the Protestant formula 'Justification by Faith Alone'). New Christians might begin believing that they made a decision for Jesus, but later realize that they received faith by the grace of Jesus and the power of the Holy Spirit. We may begin with our personal faith, but then realize that faith is for the whole world, not just us alone (1 Tim 4:10). The Gospel is for those who have personal faith, but it is also for those who do not yet have faith, and it also is faith "for the future of the whole suffering creation." The Gospel is for all of Creation, not just individuals who believe it, or personally accept Jesus as their savior. We are not the authors of our faith (Heb 12:2), because the ground of our faith is in the saving work of Jesus Christ alone (solus Christus), and although we are justified by faith alone (solo fide), it is not our personal faith that causes our individual salvation. Moltmann says that simple faith matures to an understanding belief, and this mature faith is much larger than our own personal faith, and extends beyond our own person to all the Heavens and the Earth. Moltmann describes mature faith as "believing with our eyes open", or as Anselm said, "faith seeking understanding". Moltmann concludes this quotation by defining theology as "the form of the knowledge of faith with respect to its life in the world."

The following quotation is from Jürgen Moltmann's Introduction to Christian Theology lectures at Duke in 1968:

For the believers it is self-evident to believe. Not faith, but rather unfaith is inexplicable. In their faith, they not only accept as true the personal significance that Christ holds for them, but they also know him as he is in himself and therefore as he is for all mankind. In Peter's confession we read: "We have believed, and have come to know that you are the Holy One of God" (John 6:69). . . . I want to give an example of the importance of this argument. I quote a declaration of American Southern Baptists. They write: "We have reduced in some way the range of the Christian Confession by having substituted the original version 'Jesus Christ the Lord', which expresses the triumph and the largeness, comprehending heaven and earth, of God's deed, with the diminutive formula 'I accept Jesus Christ as my savior'. Although those who pretend to keep closest to the Bible insist on the second sentence, it occurs nowhere in the New Testament. And there is little justification for it. It diminishes the great miracle of the Christian Gospel into the handy form of an introverted and self-centered individualism." Here then we can elucidate the problem with some precision: There is no other approach to Jesus the Savior except by faith in his Word. But in faith we find in Jesus the author of the salvation of the whole creation and not only our own. Because it is not our believing which makes him a savior to us, but he who makes us believers, we find him as he is in himself and for everyone whenever we being to believe in him. This is the significance of the sentence that the ground of faith is more than faith and, naturally, more than my own faith. For I expect him to be the ground not only of my faith but of the faith of those who do not yet believe, and I expect him to be the ground not only of faith, but also of a renewed world ("the Lord both of the dead and of the living" Rom 14:9). There is more of him for the future of the whole suffering creation that comes out in his significance for me in my faith. Therefore, it seems to me, that we always start with the belief that he is "my" savior and come to age in belief that he is "the" savior. Exactly this is the way from simple belief (fides implicita) to a mature belief (fides explicita). It is the way from simple belief into understanding belief. Thus we can see that knowledge is inevitably necessary to Christian faith. Theology is the form of the knowledge of faith with respect to its life in the world. [1] Jürgen Moltmann

References:

[^1] Moltmann, Jürgen. An Introduction to Christian Theology. Ed. Douglas Meeks. N.p.: Duke, 1968. 30-31. Print.