Prayer when entering and leaving mosques

Hazrat Fatima^ra, the daughter of the Holy Prophet^sa, said:

“Whenever the Messenger of Allah entered the mosque, he would say:

بِسْمِ اللهِ وَالسَّلَّامُ عَلَى رَسُولِ اللهِ اللَّهُمَّ اغْفِرْلِی ذُنُوبِی وَافْتَحْ لِي أَبْوَابَ رَحْمَتِكَ

“‘In the name of Allah; peace be on the Messenger of Allah. O my Lord, forgive me my sins and open the gates of Thy mercy to me.’

“When he would leave the mosque he would say:

بِسْمِ اللهِ وَالسَّلَّامُ عَلَى رَسُولِ اللهِ اللَّهُمَّ اغْفِرْلِی ذُنُوبِی وَافْتَحْ لِي أَبْوَابَ فَضْلِکَ

“‘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.’”

(Sunan Ibn Majah, Kitab al-Masajid wal-Jamaat)