"To abandon the church" means to stop being a member or participant in a religious institution and not follow its teachings or practices anymore. Full definition
In reality, I've abandoned the church institution in order to make my own hospital ship, so to speak. (nakedpastor.com)
There could be an honest discussion throughout the church, involving also many who have abandoned the church about the wide range of complex issues involved in sexual relations. (religion-online.org)
The lawsuit was dropped once the school district agreed to abandon the church venue for school functions. (law.stackexchange.com)