Peter indicates that the healing of the lame man should not have amazed the Jews and that it was not done through the power or piety of Peter and John but through the Name of Jesus. He goes on to preach a sermon in which he first lays at their feet the sin of having abandoned Christ to death and asking for a murderer to be released in His place. He then offers them the hope of salvation through the very death they had brought about. He concludes by urging them to repent and turn to Christ that they might be forgiven.
We apply these events to our own circumstances today, seeing how it is that we should engage in evangelism. At the same time, unbelievers are urged to listen to the voice of Jesus and come to Him for salvation.