Perhaps I'm being pedantic, but Lot was not a "Christian" per se. He was referred to by Peter as a "righteous" man. The term "Christian" was given to followers of Christ after His ascension. Lot, because he was called righteous, COULD be considered like Abel, Noah, Abraham, Job, David, Elijah, Joshua, Moses, Gideon, Deborah, Hezekiah, Esther, Daniel, etc.
Granted, Lot lived as a "carnal Christian" would have lived (as referred to by Paul).