Sayyiduna Anas (may Allah be pleased with him) narrates: We used to come to the mosque of the Prophet (peace and blessings of Allah be upon him), and we used to sleep there, but we would not perform ablution again (after sleeping). This narration is authentic.

Sayyiduna Anas (may Allah be pleased with him) narrates: I have seen the companions (may Allah be pleased with them) of the Noble Prophet (peace and blessings be upon him); they would be made to stand for prayer, to the extent that sometimes I would even hear some of them snoring, but then they would get up and perform the prayer and would not perform ablution again. The narrator named Ibn Mubarak stated this: "According to us, this ruling is when they would fall asleep while sitting." This hadith is authentic.

Sayyiduna Anas (may Allah be pleased with him) narrates: The companions (may Allah be pleased with them) of the Prophet (peace and blessings be upon him) used to wait for the call to the ‘Isha prayer, until their heads would droop (i.e., they would fall asleep), then they would get up and perform the prayer without renewing their ablution. This narration is authentically transmitted.