Donohue has called on Lohan to apologize for her crucifixion pose for Purple Fashion magazine.
The mag's cover shows the troubled actress dressed in white, with a crown of thorns on her head and her arms outstretched.
Donohue slammed Lohan as "spiritually homeless," and said she would suffer bad karma if she didn't apologize soon.
Lohan, an ex-Catholic, recently said, "I’m all about Karma…what goes around comes around.”
"If she believes that, then it behooves her to apologize to Christians before it’s too late," Donohue said.
"Looks like Tiger Woods is not the only celebrity who would benefit by converting to Christianity these days. Forgiveness occupies a central place in Christianity, but the predicate to forgiveness is repentance."