اَللَّهُمَّ اغْفِرْ لِي ذُنُوْبِي وَافْتَحْ لِي أَبْوَابَ رَحْمَتِكَ
Transliteration
Rabbig-firli dhunubi waftah li abwaaba rahmatik
Translation
O Allah, forgive me my sins and open to me the gates of Your mercy.
Prophet Muhammad (ﷺ) said Durood first when entering the mosque. After that, he said:
اَللَّهُمَّ اغْفِرْ لِي ذُنُوْبِي وَافْتَحْ لِي أَبْوَابَ رَحْمَتِكَ
Transliteration
Rabbig-firli dhunubi waftah li abwaaba rahmatik
Translation
O Allah, forgive me my sins and open to me the gates of Your mercy.
This dua cleans your heart from sins. It calls Allah's mercy around you. Your mind becomes ready for prayer and worship in the masjid.
The Sunnah dua is Allahummagh-firli dhunubi waftah li abwaba rahmatik. It means ask Allah to forgive you and open mercy for you.
Right foot first, then say the dua softly. Ask Allah for forgiveness and blessings as you step inside the mosque.
It gets your heart ready for prayer. Leave the world outside. Seek Allah's mercy inside.
You can understand it in English. But Arabic words are Sunnah. Try to learn and say the Arabic dua.
We ask Allah hoping He forgives. You are speaking to Him directly at His house door. Allah hears you.
It asks for mercy. Allah's mercy covers everything good including rizq. So yes, it includes that blessing.
Say it when you remember inside. Allah sees you tried. He knows your heart wanted to follow Sunnah.
Dua to Say When You Enter the Masjid
Dua When You Enter The Mosque (Allahumma Salli Ala Muhammad)
Dua You Say Before Going Into Mosque (Auzubillah)
Dua When You Leave The Masjid (Allahumma Inni As Aluka)
Dua After Leaving The Masjid (Wassalatu Wassalamu)
Prayer When Exiting the Masjid (Allahumma Ajirni)