NOTES for Act 2:37-38
As can be seen, the people who heard Peter took his preaching seriously. The question "what then shall we do?" did not sound by accident. Indeed, if the issue is rejection of the Messiah Himself, and conscious rejection at that, one cannot escape the consequences of such a sin. Both Yahwism and Judaism traditionally looked at conscious sin as something whose consequences weigh over a person endlessly, even if that person deeply and sincerely repents of what he has done. And here the sin was participation in the death of the Messiah... There was something to think about and something to fear.
Peter immediately points his listeners to the only possible way out of the situation. A way out made possible precisely thanks to the One whom, according to the apostle's word, people killed and God raised. This way out is connected with the possibility of sharing in that new life, the life of the Kingdom, which on the day of Pentecost became a reality open to everyone.
Entering the Kingdom, a person begins his life anew. From a clean sheet. The consequences of all sins he committed remain in the former life, provided, of course, that the person does not drag them along with him. And for this not to happen, that very conversion of which the evangelist speaks is necessary. In the Synodal translation it is traditionally called repentance, but the issue is precisely conversion; the corresponding Greek word of the original, at least, means exactly this. And conversion is not only a return to God, from whom one had turned away. Nor is it only emotional repentance for committed sins.
It is also the comprehension of what was done, awareness of the spiritual quality of one's actions and of the intentions standing behind them. And a conscious rejection of those intentions that are incompatible with the Torah, with the Gospel, with the commandments given by God. Then one can indeed begin a new life from a clean sheet. Then the community life of which the author of Acts speaks could also become reality, for it can exist only as long as each member of this community lives the life of the Kingdom in all the fullness available to him. As it ought to be in the Church with a capital letter.