Assalamu aleikum,
AS abu lahab was a son of abdul muttalib
so he was uncle of Muhammad (saw) and pegan of arab, most probably he was on his parents religion.
His wife often left firewood on the path of our beloved prophit (saw), and abu lahab threw intestines of pigs over Muhammad (saw). Also abu lahab threw a stone at Muhammad (saw) when he tried to warn the Quraish. Abu lahab had a very red complexion that is why he was called this way. According to scholars, Muhammad (saw) strangled Umm, so she throw no more thorns at him.
Hadith says:
Hadhrat Urwah (May Allah SWT be well pleased with him) says, �Thuwaybah (May Allah SWT be well pleased with him) was a slave of Abu Lahab. Abu Lahab set her free, and she suckled the Holy Prophet (Sallallahu alaihi wa sallam). When Abu Lahab died, someone from his family saw him in a dream, in the worst possible condition. The person asked him, �What did you get?� Abu Lahab said, �After I was separated from you, I did not find any peace, except that because I freed Thuwaybah (May Allah SWT be well pleased with her), I am given a drink through this (i.e. the finger). Verily, my wife is much better of (i.e. in Jannah).