‘A'isha said that when God’s messenger sat in an assembly or prayed he spoke some words, so she asked him about them. Saying that they were, “Glory be to Thee, O God, and I begin with praise of Thee; there is no god but Thou; I ask forgiveness of Thee and turn to Thee in repentance,” he told her that if one speaks what is good this will act as a seal on his words till the day of resurrection, and that if one speaks what is evil this will act as an atonement for what he has said.
Nasa’i transmitted it.