When anyone amongst you dozes in prayer, he should sleep, till sleep is gone, for when one of you prays while dozing he does not know whether he may be asking pardon or vilifying himself.
Sahih Muslim Book 6, Hadith 263
← Previous Hadith The Messenger of Allah (ﷺ) came to me when a woman was sitting with me. He said: Who is she? I said: She is a woman who does not sleep but prays. He said: Do such acts which you are capable of doing. By Allah, Allah does not grow weary but you will grow weary. The religious act most pleasing to Him is one the doer of which does it continuously. (And in the hadith transmitted by Abu Usama :" She was a woman from Banu Asad." )

Sahih Muslim Book 6, Hadith 262 Next Hadith → When any one of you gets up at night (for prayer) and his tongue falters in (the recitation) of the Qar'an, and he does not know what he is reciting, he should go to sleep.

Sahih Muslim Book 6, Hadith 264