'Promise' in the Bible

This is what I mean: The Law that came 430 years later did not cancel the covenant that God ratified previously. The promise was never nullified.

For if the inheritance comes about through the Law, it no longer comes about through the promise. But it was through a promise that God so graciously gave it to Abraham.

Why, then, was the Law added? Because of transgressions, until the descendant came about whom the promise pertained. It was put into effect through angels by means of a mediator.

And if you belong to the Messiah, then you are Abraham's descendants indeed, and heirs according to the promise.

Now the slave woman's son was conceived through human means, while the free woman's son was conceived through divine promise.

So you, brothers, are children of the promise, like Isaac.