Selected Sayings of The Holy Prophet of Islam — Page 23
30. Fatimah az Zahra, God be pleased with her, narrates that when the Holy Prophet, peace and blessings of Allah be upon him, entered the mosque, he would recite the following prayer: "In the name of Allah; peace be on the Messenger of Allah. 0, my Lord forgive me my sins, and open the gates of Thy mercy to me. " And when he departed from the mosque, he would offer the following prayer: "In the name of Allah; peace be upon the Messenger of Allah. Forgive me my sins, my Lord and open the gates of Thy grace to me. " (Musnad Ahmad) 23