Dua before sleeping — protect me from punishment
اللّهُـمَّ قِنـي عَذابَـكَ يَـوْمَ تَبْـعَثُ عِبـادَك
اللّهُـمَّ قِنـي عَذابَـكَ يَـوْمَ تَبْـعَثُ عِبـادَك
Allahumma qinee AAathabaka yawma tabAAathu AAibadak
Translation
O Allah, protect me from Your punishment on the day Your servants are resurrected.
When to recite
Recited three times when lying down to sleep.
Source / Reference
Abu Dawud 4/311, At-Tirmithi 5/473