Narrated Abu Mas`ud:

When the verses of charity were revealed, we used to work as porters. A man came and distributed objects of charity in abundance. And they (the people) said, "He is showing off." And another man came and gave a Sa (a small measure of food grains); they said, "Allah is not in need of this small amount of charity." And then the Divine Inspiration came: "Those who criticize such of the believers who give in charity voluntarily and those who could not find to give in charity except what is available to them." (9.79).

Narrated Abu Mas`ud:

When we were ordered to give alms, we began to work as porters (to earn something we could give in charity). Abu `Aqil came with one half of a Sa` (special measure for food grains) and another person brought more than he did. So the hypocrites said, "Allah is not in need of the alms of this (i.e. Abu `Aqil); and this other person did not give alms but for showing off." Then Allah revealed:-- 'Those who criticize such of the Believers who give charity voluntarily and those who could not find to give in charity except what is available to them.' (9.79)

Abu Mas'ud reported: We were commanded to give charity (despite the fact.) that we were coolies. Abu 'Aqil donated half a sa'. And there came another man with more than this. The hypocrites said: Verily Allah does not stand in need of the charity of this, and the second one has done nothing but only made a show (of his charity). Then this verse was revealed." Those who scoff at the voluntary givers of charity among the believers as well as those who cannot find anything (to give) but with their hard labour" (ix. 80). And Bishr did not utter the word Muttawwi'in.