But now in Christ Jesus you who formerly were far off have been brought near by the blood of Christ. Though, in the future they will be grafted back into the people of God. Therefore I say to you, the kingdom of God will be taken away from you, and be given to a nation producing the fruit of it. These are the words that you shall speak to the sons of Israel. Keeping covenant is simply a single term for the relationship of faith and works that the Bible presents in both testaments.
Faith is the horse and works are the cart.
You see that a man is justified by works, and not by faith alone. The message of reconciliation which is to be proclaimed to the world is the promise of the new covenant. He has committed to us the word of reconciliation. In the church's sacraments, covenant faithfulness is pledged. Abraham was chosen by God in order that he carry out the familial covenantal responsibilities of instructing his children in faithfulness to God.