The key to all assistive technology is that it bypasses ambient noise and comes directly to whatever type of hearing device you are using. It sounds as if your church has an FM system installed. You are using a device called a receiver which is a bit like a portable radio. You connect earbuds or a headset to it.

People who use hearing aids equipped with telecoils can plug a neckloop into that receiver and get the sound loud and clear too. When people tell me that hearing aids didn't work well for them I wonder if the person who sold them explained the options that bring sound directly to the hearing instrument in places like churches, theaters, performing arts centers, meeting rooms, etc. I encourage everyone who is trying hearing aids for the first time to insist on learning about those options and trying them before they buy. Providers who sell hearing aids should be required to explain and demonstrate this. A shame they are not.