Romans 4:13-16

For the promise to Abraham or to his descendants that he would be heir of the world was not through [observing the requirements of] the Law, but through the righteousness of faith. [Gen 17:4-6; 22:16-18] If those who are [followers] of the Law are [the true] heirs [of Abraham], then faith [leading to salvation] is of no effect and void, and the promise [of God] is nullified. For the Law results in [God’s] wrath [against sin], but where there is no law, there is no violation [of it either]. Therefore, [inheriting] the promise depends entirely on faith [that is, confident trust in the unseen God], in order that it may be given as an act of grace [His unmerited favor and mercy], so that the promise will be [legally] guaranteed to all the descendants [of Abraham]—not only for those [Jewish believers] who keep the Law, but also for those [Gentile believers] who share the faith of Abraham, who is the [spiritual] father of us all