No verse tells us that faith comes by hearing, and hearing by the word of God either. No verse says that the natural man doesn't receive the things of God either. But both those things were always true. They didn't become true at the time they were written.told you you'd say something like that ...
No verse tells us he was regenerated before he left Ur of Chaldees or when he left Haran. No verse which tells us that faith was imputed to Abraham before he believed in Gen 15. No verse which tells us that righteousness was imputed to Abraham before he believed in Gen 15.
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Again, the Bible is a book that gives progressive revelation. Truth is true whether it is revealed or not.