It does not say, "Lutherans believe that our various 300+ denominations save a person," A church doesn't save, God does. He may do so via means but using means doesn't negate that it's God doing it. But clearly, Lutherans do not teach that a church (any church) saves.
I've never known a non-denom parish that clearly printed exactly what that church teaches. They seem to go to great lengths to leave that very unclear. Or we get entirely meaningless things like "We teach what the Bible does" or "We teach what is true."
If you ask, Lutherans have it printed out. It's the Book of Concord. I have one. It's 648 pages long, but it references much more than that in previous statements.
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