Khalid bin Ma'dan خالد بن معدان · General Behavior (Kitab Al-Adab)

The Messenger of Allah (ﷺ) used to say when he lay down: O Allah, I seek refuge in Thy noble Person and in Thy perfect Words from the evil of what Thou seizest by its forelock; O Allah! Thou removest debt and sin; O Allah! thy troop's not routed, Thy promise is not broken and the riches of the rich do not avail against Thee. Glory and praise be unto Thee!.

Recite (the Surah) 'Say, O you disbelievers!' and then go to sleep at its end, for it is a declaration of freedom from polytheism.