On the authority of Abu Hurrairah (radiallaahu ‘anhu): The Prophet (salallaahu ‘alaihi wa sallam) said:

The one who looks after a widow or a poor person is like a Mujaahid (fighter) who fights for Allaah’s cause, or like him who performs prayers all the night and fasts all the day.

[Bukhaaree; The Book of Supporting the Family]