This is the end of the part of the story that happened on the Day of Pentecost. Verse 42 begins a section that explains how the believers continued to live after the Day of Pentecost. (See: [[rc://en/ta/man/translate/writing-endofstory]])
"he seriously told them and begged them." Here the words "testified" and "urged" share similar meanings and emphasize that Peter urged them strongly to respond to what he was saying. AT: "he strongly urged them" (See: [[rc://en/ta/man/translate/figs-doublet]])
The implication is that God will punish "this wicked generation." AT: "Save yourselves from the punishment that these wicked people will suffer" (See: [[rc://en/ta/man/translate/figs-explicit]])