Narrated by Sayyiduna Abdullah bin Amr bin al-As (may Allah be pleased with him), he says: I presented myself before the Messenger of Allah (peace and blessings be upon him) and said: O Messenger of Allah! Command me regarding fasting. The Prophet (peace and blessings be upon him) said: Fast one day, and you will receive the reward of an additional nine days (because the reward of every good deed is tenfold). I said: O Messenger of Allah! I have the strength for more than this, so grant me permission to fast more. The Prophet (peace and blessings be upon him) said: Fast two days, and you will receive the reward of an additional eight days. But I again said: O Messenger of Allah! I have the strength for more than this, so grant me permission for more fasting. The Prophet (peace and blessings be upon him) said: Fast three days, and you will receive the reward of an additional seven days. But with my repeated requests, the Prophet (peace and blessings be upon him) kept allowing for more action (and reducing the reward), until the Prophet (peace and blessings be upon him) said: The best fasts are those of my brother Dawud (peace be upon him), and that is to fast one day and leave one day. When Sayyiduna Abdullah became old, he used to say: I wish I had sufficed with the first command of the Noble Prophet (peace and blessings be upon him).