The Book of Prayers (Kitab Al-Salat)

Muslim :: Book 4 : Hadith 1719

Abu Huraira reported Allah's Messenger (may peace be upon him) as saying: 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.