The church says she is a "proud, self-righteous hypocrite" and an "adulterer".
"God Almighty put a spotlight upon the proud, self-righteous hypocrites that think the same-sex marriage sin is worse than their adultery sin," the church said in a statement.
They went on to mention Ms Davis' four marriages, which it says are adulterous, claiming: "That man that Kim Davis is living with, and calling her husband, IS NOT! Her husband is Dwain Wallace, who she married when she was 18-tears-old.
"It was adultery at the beginning, adultery in the middle and it is indeed adultery today!"
Ms Davis was sent to jail for six days on 3 September for refusing to issue same-sex marriage licenses, citing her biblical opposition to same-sex marriage.
The Westboro Baptist Church, formerly led by hate preacher Fred Phelps and his immediate family, are known for protesting soldiers funerals, where they claim the deceased were killed because "god hates fags".
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