Before Going to Sleep
بِاسْمِكَ رَبِّي وَضَعْتُ جَنْبِي، وَبِكَ أَرْفَعُهُ، فَإِنْ أَمْسَكْتَ نَفْسِي فَارْحَمْهَا، وَإِنْ أَرْسَلْتَهَا فَاحْفَظْهَا بِمَا تَحْفَظُ بِهِ عِبَادَكَ الصَّالِحِينَ.
How it is read
Bismika Rabbee wada'tu jambee, wa bika arfa'uh. Fa-in amsakta nafsee farhamha, wa in arsaltaha fahfadh-ha bima tahfadhu bihi 'ibadakas-saliheen.
What it means
In Your name, my Lord, I lay down my side, and by You I raise it. If You take my soul, have mercy on it; and if You release it, protect it with that which You protect Your righteous slaves.
Where it comes from
Sahih al-Bukhari (6320), Sahih Muslim (2714)