The orientation to the “Church Catholic” is, no doubt, a tremendous asset of Lutheranism.
What happens if an issue comes up that is not in the Book of Concord and not expressly stated in the Scripture?
For example, did anyone a short century ago foresee the gay “marriage”?
Is contraception treated in any way? I know that prior to 1930 every Christian community of faith considered contraception sinful. Now none in the Protestant (using the term loosely) world does.
There is no Lutheran confession I'm aware of addressing birth control in the context of a marriage, but it is recognized that marriage is an institution ordained by God for the mutiplication of His people (Genesis 1:28).