Galatians 3:19-21

Amplified Bible

¹⁹ Why, then, the Law [what was its purpose]? It was added [after the promise to Abraham, to reveal to people their guilt] because of transgressions [that is, to make people conscious of the sinfulness of sin], and [the Law] was ordained through angels and delivered to Israel by the hand of a mediator [Moses, the mediator between God and Israel, to be in effect] until the Seed would come to whom the promise had been made. ²⁰ Now the mediator or go-between [in a transaction] is not [needed] for just one party; whereas God is only one [and was the only One giving the promise to Abraham, but the Law was a contract between two, God and Israel; its validity depended on both]. ²¹ Is the Law then contrary to the promises of God? Certainly not! For if a system of law had been given which could impart life, then righteousness (right standing with God) would actually have been based on law.