18. For if the inheritance [of the promise depends on observing] the Law [as these false teachers would like you to believe], it no longer [depends] on the promise; however, God gave it to Abraham [as a free gift solely] by virtue of His promise.
19. What then was the purpose of the Law? It was added [later on, after the promise, to disclose and expose to men their guilt] because of transgressions and [to make men more conscious of the sinfulness] of sin; and it was intended to be in effect until the Seed (the Descendant, the Heir) should come, to and concerning Whom the promise had been made. And it [the Law] was arranged and ordained and appointed through the instrumentality of angels [and was given] by the hand (in the person) of a go-between [Moses, an intermediary person between God and man].
20. Now a go-between (intermediary) has to do with and implies more than one party [there can be no mediator with just one person]. Yet God is [only] one Person [and He was the sole party in giving that promise to Abraham. But the Law was a contract between two, God and Israel; its validity was dependent on both].
21. Is the Law then contrary and opposed to the promises of God? Of course not! For if a Law had been given which could confer [spiritual] life, then righteousness and right standing with God would certainly have come by Law.
22. But the Scriptures [picture all mankind as sinners] shut up and imprisoned by sin, so that [the inheritance, blessing] which was promised through faith in Jesus Christ (the Messiah) might be given (released, delivered, and committed) to [all] those who believe [who adhere to and trust in and rely on Him].
23. Now before the faith came, we were perpetually guarded under the Law, kept in custody in preparation for the faith that was destined to be revealed (unveiled, disclosed),