Note 16 at Gal. 2:21: Paul's statement implies that the grace of God can be frustrated. The word frustrate means "to prevent from accomplishing a purpose of fulfilling a desire; nullify." The purpose of God's grace in our lives is to set us free from every device of Satan (1 Jn. 3:8) and grant us abundant life (see note 6 at Jn. 10:10, p. 301). This will not come to pass if we are striving to approach unto God through keeping the law.

Note 17 at Gal. 2:21: What a statement!! This should leave no doubts about whether we can be justified through the law. "For Christ is the end of the law for righteousness. . ." (Rom. 10:4), so anyone who is trusting in the law is not trusting in Christ.