It is narrated from Sayyiduna Talha bin Ubaidullah, may Allah be pleased with him, that he said: A man from Najd came to the Messenger of Allah, peace and blessings be upon him. His hair was disheveled and his voice was buzzing, but his words were not understood until he came close. Then he asked the Messenger of Allah, peace and blessings be upon him, about the meaning of Islam. The Prophet, peace and blessings be upon him, said:“To perform five prayers in the day and night.”The man said: Is there any prayer upon me other than these? The Prophet, peace and blessings be upon him, said:“No, unless you perform voluntary prayers.”The Prophet, peace and blessings be upon him, said:“And fasting in Ramadan.”He said: Is there any other fasting upon me besides this? The Prophet, peace and blessings be upon him, said:“No, unless you fast voluntarily.”Then the Prophet, peace and blessings be upon him, mentioned Zakat. The man said: Is there any charity obligatory upon me besides this? He said:“No, unless you give voluntarily.”Then the man turned his back and left. The Messenger of Allah, peace and blessings be upon him, said:“He will succeed if he speaks the truth.”

It is narrated from Sayyiduna Abu Huraira, may Allah be pleased with him, that the Messenger of Allah, peace and blessings be upon him, said: "When a person goes to sleep, Satan ties three knots at the back of his head. With every knot, he strikes and says: 'You have a long night ahead, so sleep.' If the person wakes up and remembers Allah, one knot is untied. If he performs ablution, the second knot is untied. Then if he performs the morning prayer, the third knot is untied. Thus, that person remains cheerful and good-natured for the day; otherwise, he remains ill-tempered and lazy."