Hazrat Anas (may Allah be pleased with him) narrates that the Messenger of Allah (peace and blessings be upon him) once came and saw a rope tied. He asked, "What is this?" He was told, "O Messenger of Allah! Such-and-such woman prays, and when she gets tired, she leans on this rope for support." The Prophet (peace and blessings be upon him) said, "One should pray as long as one is energetic, and when one gets tired, one should sleep."