Abu Ayyub Al-Ansari (May Allah be pleased with him) reported: The Prophet (PBUH) said: "He who utters ten times: `La ilaha illallahu, wahdahu la sharika lahu, lahulmulku wa lahulhamdu, wa Huwa `ala kulli sha'in Qadir (there is no true god except Allah. He is One and He has no partner with Him. His is the sovereignty and His is the praise, and He is Omnipotent),' he will have a reward equal to that for freeing four slaves from the progeny of Prophet Isma`il.''
[Al-Bukhari and Muslim]. Commentary: "Slaves from the progeny of Isma`il'' is a simile for very precious slaves. That is, it has the same reward to which the emancipation of four very precious slaves is eligible.
