Narrated Abu Al-Mahh [??]: We were with Buraida in a battle on a cloudy day and he said, "Offer the `Asr prayer early as the Prophet said, "Whoever leaves the `Asr prayer, all his (good) deeds will be annulled."

Narrated Ibn Abu Malih [??]: I was with Buraida on a cloudy day and he said, "Offer the `Asr prayer earlier as the Prophet said, 'Whoever leaves the `Asr prayer will have all his (good) deeds annulled." (See Hadith No. 527 and 528)

Narrated `Abdullah bin `Amr: Allah's Apostle was informed about my fasts, and he came to me and I spread for him a leather cushion stuffed with palm fires, but he sat on the ground and the cushion remained between me and him, and then he said, "Isn't it sufficient for you to fast three days a month?" I replied, "O Allah's Apostle! (I can fast more)." He said, "Five?" I replied, "O Allah's Apostle! (I can fast more)." He said, "Seven?" I replied, "O Allah's Apostle! (I can fast more)." He said, "Nine (days per month)?" I replied, "O Allah's Apostle! (I can fast more)" He said, "Eleven (days per month)?" And then the Prophet said, "There is no fast superior to that of the Prophet David it was for half of the year. So, fast on alternate days."

Narrated `Abdullah bin `Amr: The news of my fasting was mentioned to the Prophet . So he entered upon me and I put for him a leather cushion stuffed with palm-fibres. The Prophet sat on the floor and the cushion was between me and him. He said to me, "Isn't it sufficient for you (that you fast) three days a month?" I said, "O Allah's Apostle! (I can fast more than this)." He said, "You may fast) five days a month." I said, "O Allah's Apostle! (I can fast more than this)." He said, "(You may fast) seven days." I said, "O Allah's Apostle!" He said, "Nine." I said, "O Allah's Apostle!" He said, "Eleven." I said, "O Allah's Apostle!" He said, "No fasting is superior to the fasting of (the Prophet David) which was one half of a year, and he used, to fast on alternate days. (See Hadith No. 300, Vol 3)