the Messenger of Allah (ﷺ) said: “Whoever enters the marketplace and says: ‘There is none worthy of worship except Allah, Alone, without partner, to Him belongs the dominion, and to Him is all the praise, He gives life and causes death, He is Living and does not die, in His Hand is the good, and He has power over all things, (Lā ilāha illallāh, waḥdahu lā sharīka lahu, lahul-mulku wa lahul-ḥamdu, yuḥyī wa yumītu, wa huwa ḥayyun lā yamūtu, biyadihil-khairu, wa huwa `alā kulli shay’in qadīr)’ Allah shall record a million good deeds for him, wipe a million evil deeds away from him, and raise a million ranks for him.”
Jami` at-Tirmidhi Book 48, Hadith 59
The news of my fasting was mentioned to the Prophet (ﷺ) . So he entered upon me and I put for him a
leather cushion stuffed with palm-fibres. The Prophet (ﷺ) 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 Messenger (ﷺ)! (I can fast more than this)." He said, "You may fast) five days a month." I said, "O
Allah's Messenger (ﷺ)! (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 Messenger (ﷺ)!" He said, "Eleven." I said, "O Allah's Messenger (ﷺ)!"
He said, "No fasting is superior to the fasting of (the Prophet (ﷺ) David) which was one half of a year, and
he used, to fast on alternate days. (See Hadith No. 300, Vol 3)
Sahih al-Bukhari Book 79, Hadith 51