The tv has been there for a while with nothing going to it. Weird I know! All I’m trying to do is get the sermon audion on the tv where people can hear. So I will need the option to mute during the worship set and than I mute for the sermon. If that makes sense.
Are you also trying to feed a video signal (say, from a camera in the sanctuary) to the TV?
If not, there's no point in trying to pipe the sound to the TV. Just use a separate amplifier and speakers for the audio. As others have mentioned, the built-in speakers on TVs are usually so-so quality, and generally don't get loud enough for a large room.
If you are feeding a video signal, then you probably want to mix the sound into the video stream. Then use the TV's audio out to an external amplifier & speaker. The reason for mixing the sound into the video stream is to make sure the audio and video are time aligned. You can do time alignment with external hardware, but that can be more difficult than just mixing the sound into the video stream.
On the other hand, if you have a pure analog signal (old tech?) for the video, then time alignment usually isn't an issue and you can feed an external amplifier & speaker separately.