Sayyiduna Abdullah bin Amr (may Allah be pleased with him) narrates: It was conveyed to the Prophet (peace and blessings of Allah be upon him) that I say: By Allah! As long as I am alive, I will fast every day and offer voluntary prayers every night. I presented myself before the Prophet (peace and blessings of Allah be upon him) and said: O Messenger of Allah (peace and blessings of Allah be upon him)! I have said this. The Prophet (peace and blessings of Allah be upon him) said: You will not be able to do this. Fast some days and leave some days. Sleep as well and offer voluntary prayers as well. Fast three days in every month. The reward of a good deed is tenfold, so this will be equivalent to fasting the whole month.