NOTES for Pe2 3:9-10
Peter reminds us of the day of Judgment. In doing so, he appears to have in mind the perplexities that were spreading among Christians already of the second, not the first, generation. The matter concerned unfulfilled expectations: both the first and the second generation of Christians expected the Savior's return literally from day to day, and still He did not return. This prolonged waiting gave rise to perplexity.
Against this background there appeared the very "scoffers" mentioned by the apostle: they openly questioned all of Christianity, being sure themselves and assuring others that there would be no return of the Savior and that all eschatology was merely an invention of a mind heated by the Christian texts that had already begun to appear.
Peter remains faithful to what he heard from his Teacher, who promised to return soon after the destruction of Jerusalem and the Temple that He had foretold. But the apostle also remembered something else: Jesus' words that not even He Himself knows the day of His return, and that all times are in the Father's power. Peter understands these words of the Savior to mean that the day of Judgment and His return is not predetermined in the sense of dates, but is inevitable because of the spiritual process that we today usually call the history of salvation. As for the dates, they are determined first of all by the spiritual condition of the Church, and also of all humanity.
The postponement of Judgment is not an indulgence for sinners, but a chance for their conversion. Of course, if God's goal were to punish sinners as strictly as possible, the day of Judgment would quite possibly have come long ago. But He has another goal: He wants as many sinners as possible to repent and turn, and therefore He leaves chances for conversion to everyone and each person as long as this has meaning. Of course, sooner or later the day will inevitably come when there is no one and nothing left to wait for.
But when it will come cannot be said exactly, and only the Father can determine the moment of its coming. This is understandable: He alone sees the whole of reality in all its fullness, and the full depth of every heart. Only He can determine when waiting no longer has meaning because everyone has already made his choice. We human beings cannot know this by definition. But we do not need to know it: what matters for us is to walk our path and reach the goal. To the Kingdom. Without waiting for the day of Judgment. All the possibilities for this have already been given to us now.