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)
Narrated Shaqiq
Abu Mas`ud Al-Ansari said, "Allah's Messenger (ﷺ), used to order us to give alms. So one of us would exert himself to earn one Mud (special measure of wheat or dates, etc.,) to give in charity; while today one of us may have one hundred thousand." Shaqiq said: As if Abu Masud referred to himself.