It is narrated from Hazrat Aisha (may Allah be pleased with her) that once the Prophet (peace and blessings be upon him) was awake at night and she was lying beside the Prophet (peace and blessings be upon him). I said, "O Messenger of Allah! What is the matter?" The Prophet (peace and blessings be upon him) said, "I wish that some righteous man from among my companions would stand guard tonight." While these words were being exchanged, I heard the sound of weapons clinking. The Prophet (peace and blessings be upon him) asked, "Who is it?" He replied, "I am Sa'd bin Malik." The Prophet (peace and blessings be upon him) asked, "What brings you here?" He replied, "O Messenger of Allah! I have come to guard you." Hazrat Aisha (may Allah be pleased with her) says that after that, during sleep, I heard the sound of the Prophet's (peace and blessings be upon him) snoring.