Bishops are human and falible.
There's a difference between a "failing" and perpetuating a failed ideology. The weakness of this bishop is of the latter category. The fact that it is in direct opposition to the scripture he purports to preach should be of some concern to the organization that promoted him.
AND, as Arrogant Bustard pointed out, some bishops are successors of Judas Iscariot, which sure sounds like they are fallible at least. Remember that references bishops. The pope is, according to Catholic definition, infallible on matters of faith and morals if not prudential decisions like appointing unworthy individuals to positions of trust.
"Bishops are human and falible."
Those choosing Bishops should exercise judgement and should know about the candidate before the appointment is made.