Change it back or we leave - This is a problem in my book. Why expect a noble to abondon something as important as their faith simply to protest an elder. It suggests that nobles should place little value in their faith.
Sack a few temples in protest - Same as above. If a character truly takes religion seriously they would never be willing to sack a temple of their faith because they feel the elders are plain wrong.
Refuse to let the priests preach in your regions - This punishes the faith not the errant elder. No truly faithful noble would do that.
Empty the temple treasuries and refuse to contribute - Once again the strength of ones faith should not allow them to take actions that truly harm their religion and not the elder causing problems.
Arrest the elder and toss him in prison - This results in you becoming an agressor and gives the elder in question a weapon to use against you, but is the best of the options presented.
In short, as things stand, the best ways for a noble to fight against elders that they believe are harming their faith is to attack the church as a whole or to abandon their faith. This really makes it hard for one to be a die hard noble of the faith.