How many years after the promise to Abraham was the Law given at Sinai?
The Law was given at Sinai 430 years after the promise to Abraham. Paul emphasizes that this covenant came 430 years later, when Israel came out of Egypt and received the Law, while other passages mention 400 or 490 years without contradiction.
Les explains that Paul is speaking of the covenant confirmed before by God in the person of Christ. The Law was itself a covenant, just like the Abrahamic covenant and the Davidic covenant. It was an agreement God made, and which He could never change or withdraw; it settled forever because God made it. This covenant, the Law, was 430 years after the promise to Abraham that out of him would come the seed. 430 years later, Israel came out of Egypt and received the Law at Sinai. Les notes that this is one place where scoffers claim Scripture contradicts itself, because it says 430 years here, another place says 400 years, and another says 490 years, but there is no contradiction.
And this I say, that the covenant, that was confirmed before of God in Christ, the law, which was four hundred and thirty years after, cannot disannul, that it should make the promise of none effect.
How many years were there between God's promise to Abraham and the giving of the Law at Sinai?
The interval was 430 years. Paul states that the covenant confirmed beforehand by God in Christ could not be annulled by the Law, which came 430 years later. Israel came out of Egypt and received the Law at Sinai four hundred thirty years after the promise to Abraham.
Where did the children of Israel receive the Law?
The children of Israel received the Law at Mount Sinai. The context explains that after Moses led them out, they went and received the Law at Mount Sinai, which occurred 430 years after Abram left Haran for Canaan, as discussed in Galatians chapter 3.