Were Falwells' dad and grandad really militant atheists?

Saw news reports saying that Rev. F's dad and granddad were "militant" atheist, according to his autobiography. I'm a wishy-washy agnostic. I find that hard to believe. Falwell use to have a TV show, "The Old Time Gospel Hour". Had a big picture hanging of Abe Lincoln. Guess nobody told Jerry, but Abe wasn't a Christian, by his own admission.