Abu Hurairah (May Allah be pleased with him) reported: Some of the poor Emigrants came to Messenger of Allah (PBUH) and said to him, "The wealthy have obtained all high ranks and everlasting bliss.'' He asked, "How is that?'' They replied: "They offer Salat as we do, and observe Saum (fasting) as we do, but they give in Sadaqah (charity) and we do not, and they emancipate slaves and we cannot.'' He (PBUH) said, "Shall I not teach you something whereby you will catch up with those who have preceded you and will get ahead of those who follow you, and no one will surpass you unless he does the same as you do?'' They said, "Surely, O Messenger of Allah.'' He said, "Say: Subhan Allah, and Allahu Akbar, and praise Him (by saying Al-hamdu lillah) thirty-three times at the end of every Salat.'' They returned to him and said: "Our brothers, the possessors of wealth, having heard what we are doing, have started doing the same.'' Messenger of Allah (PBUH) said, "This is Grace of Allah which He gives to whom He wishes.''
[Al-Bukhari and Muslim].
Commentary: The wording of the Hadith apparently reveals that Subhan Allah "Glory be to Allah'', Al-hamdu lillah "Praise be to Allah'', and Aallhu Akbar "Allah is the Greatest'' should be recited thirty-three times. If each group of words is said eleven times, the total number will become thirty-three. But Al-Hafiz Ibn Hajar believes that each formula should be uttered thirty-three times, that is to say, after each prayer "Subhan Allah'', "Al-hamdu lillah'' and "Allahu Akbar'' should be uttered thirty-three times each. But according to some Ahadith, Imam An-Nawawi is of the view that "Allahu Akbar'' should be said thirty-four times and in the end "La ilaha illallahu Wahdahu la sharika Lahu, Lahul-mulku wa Lahul-hamdu, wa Huwa `ala kulli shai'in Qadir'' (none has the right to be worshipped but Allah, He is One; He has no partners; to Him belongs the dominion and all the praise; and He has power over all things) should be recited. Should we recite them together or separately? Al-Qadi `Iyad is of the opinion that it is better to recite them separately, but Imam An-Nawawi is of the view that both ways are correct. In fact, in both ways the number remains the same. Besides, an addition must not be made to the Sunnah of Messenger of Allah (PBUH). Practically we knew that it is necessary to use the prescription of a physician without making any alteration in its elements; otherwise, it will not work properly. Similarly, there are spiritual benefits, blessings and efficacy in the number told by the Prophet (PBUH). Any alteration in it will nullify its blessing and efficacy. (Fath Al-Bari).
This Hadith reveals how fervently the Companions were inclined towards good and how concerned about surpassing those who were better than them in some forms of good deeds. Indeed, all Muslims are equal with regard to the practice of religious principles. But what gives an edge to the rich over their poor coreligionists are the financial forms of worship, that is, charity and almsgiving, which the latter are unable to do.