Abraham was 75 when the promise was given (Genesis 12:4). 25 years later, he begat Isaac at 100 years of age (Genesis 21:5), Isaac begat Jacob when he was 60 (Genesis 25:26) and Jacob went to the land of Egypt when he was 130 years of age (Genesis 47:9). Up to this it makes 215 years, after this it took 430 years when Israel left Egypt and got the “Law” at Sinai (Ex 12:40). Totally, it makes 645 years. How should this verse be understood?
ESV - 17 This is what I mean: the law, which came 430 years afterward, does not annul a covenant previously ratified by God, so as to make the promise void.
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