It is narrated from Sayyiduna Abdullah bin Amr bin al-As (may Allah be pleased with them both) that he said (on one occasion): "As long as I live I will certainly fast, and as long as I live I will certainly stand the whole night in prayer." So the Messenger of Allah (peace and blessings be upon him) said to him: "Are you the one who said: 'As long as I live I will fast continuously, and as long as I live I will stand the whole night in prayer'?" Sayyiduna Abdullah bin Amr (may Allah be pleased with them both) said: "O Messenger of Allah, I did say that." So the Messenger of Allah (peace and blessings be upon him) said: "Fast and also break your fast, pray and also sleep, and fast three days of every month, for every good deed is rewarded tenfold." He said: "I find in myself the strength for more than that." He (peace and blessings be upon him) said: "Fast one day and break your fast for two days." He said: "I find in myself the ability for something better (that is, more) than that." So the Messenger of Allah (peace and blessings be upon him) said: "Fast one day and break your fast one day." He said: "O Messenger of Allah, I find in myself even more strength than that." So the Messenger of Allah (peace and blessings be upon him) said: "There is no (fast) better than that."
Imam al-Tabarani (may Allah have mercy on him) said: "No one narrated this hadith from Isa bin al-Muttalib except Khalid bin Nizar."