His Guidance in Mentioning Allah When Entering a Mosque and Leaving It

When entering a mosque, the Prophet would recite: “A`udhu billaahil-`atheemi wa bi-wajhihil-kareemi wa bi-sultaanihil-qadeemi  minash-shaytaanir-rajeem.'' (I seek refuge in Allah, the Great and in his noble countenance and his primordial authority from Satan, the rejected. He  said, "When someone says that, Satan says: "He has been protected from me for the rest of the day

He also said: "When one of you enters the mosque, let him invoke blessings upon the Prophet Muhammad ,, and let him say: 'Allaahumma iftah lee abwaaba rahmatik' (O Allah, open for me the gates of Your mercy), and upon leaving let him say: 'Allaahumma innee as'aluka min fadhlik.' (O Allah, I ask  You of your bounty)