Talhah bin Ubaidullah (may Allah have mercy on him) says: A man from Najd came to the Messenger of Allah (peace be upon him), his hair was disheveled, and though his voice could be heard buzzing, his words were not understandable, until he came close. He asked the Prophet (peace be upon him) about Islam. The Messenger of Allah (peace be upon him) said: Five prayers are obligatory in the day and night. He asked: Is there any other prayer obligatory besides these? He replied: No! Except for voluntary prayers. The Messenger of Allah (peace be upon him) said: Fasting in the month of Ramadan is also obligatory. He asked: Is there any other fast obligatory upon me besides this? He replied: No! Except for voluntary fasts. The narrator says: The Messenger of Allah (peace be upon him) informed him about charity (zakat), he asked: Is there any other charity obligatory upon me besides this? He replied: No! Except for voluntary charity. After that, as he was leaving, he was saying: By Allah! I will neither add to this nor decrease from it. The Messenger of Allah (peace be upon him) said: If he is truthful in what he says, he will succeed.