Mosiah 25:21

therefore they did assemble themselves together in different bodies, being called Churches; every Church having their priests and their teachers, and every priest preaching the word according as it was delivered to him by the mouth of Alma;

So they met in different groups called churches. Each church had priests and teachers. Each priest taught what Alma had told him.

So they met in different groups, called churches. Each church had its own priests and teachers, and every priest taught the message exactly as Alma had given it to him.