Romans 4:2, 13-15

For if Abraham was justified by works, he has something to boast about, but not before God.

For the promise that he would be the heir of the world was not to Abraham or to his seed through the law, but through the righteousness of faith. For if those who are of the law are heirs, faith is made void and the promise made of no effect, because the law brings about wrath; for where there is no law there is no transgression.