Around AD 65 the apostle Peter was imprisoned in Rome by the emperor Nero, and he realised that he would soon be executed. Since he was an eyewitness of the ministry of Jesus, he decided to write another letter to the believers he had written to before, confirming what they had been taught about Jesus. False teachers were proposing that, since Jesus hadn’t returned already, his return couldn’t be expected at all. Because they didn’t expect any future judgment, they were living immoral lives. (Peter likely learned about the threat of these teachers from a letter sent by Jude, a brother of Jesus, to warn believers against them. Peter’s letter echoes Jude’s, but in shorter form. See Jude.)
Peter answers the false teachers by stressing that he personally saw the glory and majesty of Jesus on the sacred mountain (see Mark 9:2-13). Everyone will see this glory when Jesus returns. In powerful imagery Peter describes the false teachers’ destructive effect on the community and the judgment that awaits them. In the final section of his letter, Peter explains that the Messiah’s return has been delayed because God wants everyone to repent. Our proper response is to live good lives filled with hope, since we are looking forward to a new heaven and a new earth, where righteousness dwells.