We judge a belief based upon its validity. Does it align with God’s truth? Is it logically sound? It is consistent with reality? Is it possible and probable?
We do not condemn a belief merely because of the people who hold it. It may be a proof against the belief’s validity, but we can’t discount an idea just because someone lived it out poorly. Just because Adolf Hitler brushed his teeth says nothing to whether it was a good or bad idea. It is a good idea regardless of what he thought.
Ad hominem attacks only hurt our ability to reason. And ultimately, they will be used against the beliefs we hold dear. Because you and I both know, we aren’t the best representatives of our cherished beliefs either.