What about regeneration and evangelism?

Christ on the Cross by Carl Heinrich Bloch
Public domain via Wikimedia Commons
(updated 1/2/2023)

In discussing our inclusion in the triune life of God in and through Jesus, a question pertaining to the related issues of regeneration and evangelism often emerges. It goes something like this: Given our inclusion in Christ through his incarnation, life, suffering, death, resurrection and ascension; how are we to understand what happens to us when we are "born again" (regenerated) at the moment we turn to God in faith?

The key issue in answering this question is understanding that Jesus (who is fully God and fully human) is the beginning point and the focus of all such questions. As I've wrestled with this topic, I've been aided by Thomas Torrance in his books The Mediation of Christ and The Christian Doctrine of God. Perhaps an excerpt concerning regeneration and evangelism from The Mediation of Christ will contribute to our understanding:
It is significant that the New Testament does not use the term regeneration (Gk= paliggenesia), as so often modern evangelical theology does, for what goes on in the human heart. It is used only of the great regeneration that took place in and through the Incarnation and of the final transformation of the world when Jesus Christ will come again to judge the quick and the dead and make all things new. That is to say, the Gospel speaks of regeneration as wholly bound up with Jesus Christ himself.
....[We are] born again when Jesus Christ was born of the Virgin Mary and rose again from the virgin tomb, the first-born from the dead…[we are] hid with Christ in God and will be revealed only when Jesus Christ comes again. He took [our] corrupt humanity in his Incarnation, sanctified, cleansed and redeemed it, giving it new birth, in his death and resurrection.  In other words, our new birth, our regeneration, our conversion, are what has taken place in Jesus Christ himself, so that when we speak of our conversion of our regeneration we are referring to our sharing in the conversion or regeneration of our humanity brought about by Jesus in and through himself for our sake. In a profound and proper sense, therefore, we must speak of Jesus Christ as constituting in himself the very substance of our conversion, so that we must think of him as taking our place even in our acts of repentance and personal decision, for without them all so-called repentance and conversion are empty. Since a conversion in that truly evangelical sense is a turning away from ourselves to Christ, it calls for a conversion from our in-turned notions of conversion to one which is grounded and sustained in Christ Jesus himself (pp. 85-86). 
Of course this vision of our inclusion in Christ causes us to think about our evangelistic invitations. To what are we inviting people? Torrance continues:
The Gospel is to be proclaimed in such a way that full place is given to the man Jesus in his Person and Work as the Mediator between God and man... [a message of] unconditional grace and reconciling exchange. The pattern had already been clearly set by our Lord when he proclaimed that all who wished to be his disciples must renounce themselves, or give up all right to themselves, take up the cross and follow him, and when he laid it down as a basic principle that those who want to save their lives will lose them. Face to face with Christ all would-be followers find themselves called into radical question, together with their preconceptions, self-centered desires and self-will, for to have him as Lord and Savior means that he takes their place in order to give them his place. The preaching of the Gospel in that radical form is not easy, for when we call upon people to repent and believe in Jesus Christ that they may be saved, we have a great difficulty in doing that in such a way that we do not throw people back upon themselves in autonomous acts of personal repentance and decision, or encourage them to come to Christ for their own sake rather than for Christ’s sake, in direct conflict with the very principle about motives laid down by Jesus.
There is, then, an evangelical way to preach the Gospel and an unevangelical way to preach it. The Gospel is preached in an unevangelical way, as happens so often in modern evangelicalism, when the preacher announces: this is what Jesus Christ has done for you, but you will not be saved unless you make your own personal decision for Christ as your Savior. Or: Jesus Christ loved you and gave his life for you on the Cross, but you will be saved only if you give your heart to him. In that event what is actually coming across to people is not a Gospel of unconditional grace but some other Gospel of conditional grace which belies the essential nature and content of the Gospel as it is in Jesus. 
How, then, is the Gospel to be preached in a genuinely evangelical way? Surely in such a way that full and central place is given to the vicarious humanity of Jesus as the all-sufficient human response to the love of God which he has freely and unconditionally provided for us. We preach and teach the Gospel evangelically, then, in such a way as this: God loves you so utterly and completely that he has given himself for you in Jesus Christ as his beloved Son, and has thereby pledged his very Being as God for your salvation. In Jesus Christ God has actualized his unconditional love for you in your human nature in such a once for all way, that he cannot go back upon it without undoing the Incarnation and the Cross and thereby denying himself, Jesus Christ died for you precisely because you are sinful and utterly unworthy of him, and has thereby already made you his own before and apart from you every believing in him. He has bound you to himself by his live in a way that he will never let you go, for even if you refuse him and damn yourself in hell his love will never cease. Therefore, repent and believe in Jesus Christ as your Lord and Savior. From beginning to end what Jesus Christ has done for you he has done not only as God but as man. He had acted in your place in the whole range of your human life and activity, including your personal decisions and your responses to God’s love and even your acts of faith. He has believed for you, fulfilled your human response to God, even made your personal decision for you, so that he acknowledge you before God as one who has already responded to God in him, who has already believed in God through him, and whose personal decision is already implicated in Christ’s self-offering to the Father, in all of which he has been fully and completely accepted by the Father, so that in Jesus Christ you are already accepted by him. Therefore, renounce yourself, take up your cross and follow Jesus as you Lord and Savior. 
To preach the Gospel of the unconditional grace of God in that unconditional way is to set before people the astonishing good news of what God has freely provided for us in the vicarious humanity of Jesus. To repent and believe in Jesus Christ and commit myself to him on that basis means that I do not need to look over my shoulder all the time to see whether I have really given myself personally to him, whether I really believe and trust him, whether my faith is at all adequate, for in faith it is not upon my faith, my believing or my personal commitment that I rely, but solely upon what Jesus Christ has done for me in my place and on my behalf, and what he is and always will be as he stands in for me before the face of the Father. That means that I am completely liberated from all ulterior movies in believing or following Jesus Christ, for on the ground of his vicarious human response for me, I am free for spontaneous joyful response and worship and service as I could not otherwise be (pp. 93-95).