358. Best Masnoon Dua for Entering Mosque In Islam
When entering the mosque, say -
اَللَّهُمَّ اعْصِمْنِي مِنَ الشَّيْطَانِ الرَّجِيمِ
اَللّٰهُمَّ اعْصِمْنِيْ مِنَ الشَّيْطَانِ الرَّجِيْمِ
Allaahumma`simni min ash-shaytaanir-rajeem
Translation
O Allah, protect me from Satan the outcast.