If the law could give us Abraham’s blessing, then the promise would not be necessary. But that is not possible, because God freely gave his blessings to Abraham through the promise he had made.
If we are God’s children, we will receive blessings from God together with Christ. But we must suffer as Christ suffered so that we will have glory as Christ has glory.
By saying these things I am not going against God’s grace. Just the opposite, if the law could make us right with God, then Christ’s death would be useless.
But those who depend on following the law to make them right are under a curse, because the Scriptures say, “Anyone will be cursed who does not always obey what is written in the Book of the Law.”
God made promises both to Abraham and to his descendant. God did not say, “and to your descendants.” That would mean many people. But God said, “and to your descendant.” That means only one person; that person is Christ.