I'm not aware of any certain way to leave a church other than notifying the Pastor; or, if you hold a position you may want to request a moment or two up front and announce to everyone you're leaving and say your goodbyes. In my church, there have been some announcements of moving out of state. They asked for the Pastor's blessings as they move forth and he prayed over them and anointed them with oil. However if you're just leaving because you're unhappy or have not been fulfilled in the church, then I don't think it's necessary to make an announcement unless you want to. I would just send a letter withdrawing my membership, thank whomever you'd like, and move on.
If you want your family to say, "farewell" the correct way to tell them to do so is by saying, "family say, farewell."
farewell = nana
Bid their farewell means for someone to say goodbye.
You say it "Doviđenja"
It depends on how you are using it in the sentence. For example, you could say "Will your family go to church this Sunday?" or "My family goes to church each Sunday." Both are correct.
Satan said farewell to Heaven when he challenged God.
Thank you (fa'afetai); farewell (tofa).
* Sayonara
Farvel
farvel
Totsiens
dowidzenia