I am guessing UMC = United Methodist Church, such as the one that was vandalized. Perhaps the poster is saying maybe the young thug is actually a former Methodist, now in a state of doubt and disbelief, now having fallen from grace.
I could be wrong.
It does seem like an unusual observation.
We have a story about vandalism at a church, and someone says that there are apostates in that denomination. I am confused by what one has to do with the other, and hope he comes back to explain what he’s talking about.