Matthew has the words, ‘This is the blood of the covenant [the new covenant] shed for the remission of sins.’ Here in Mark it is put more briefly: ‘the blood of the new testament.
If Christ ratified the new covenant, what is the old covenant? It is a covenant of works. There in the Garden of Eden, God made a covenant of works. The covenant was between God and man. A covenant isn’t mentioned there in connection with the Garden of Eden, but that is what it was: an arrangement between God and our first parents. The arrangement, the covenant, ran along these lines: if Adam, our representative head, would obey God in that perfect, wonderful environment, then mankind would have eternal blessing and God would be their God for ever. There was one condition for obedience, only one: that they would not take of the fruit of the tree of the knowledge of good and evil. But our first parents disobeyed God and they wanted to know things that God was not permitting them to know. They felt they were being deprived and they disobeyed him and they fell from his wonderful promises of protection, and the whole human race fell with them. Although this covenant was broken in Eden and afterwards could only bring condemnation, it was still in force. The covenant made with Israel on Sinai was a re-iteration of the covenant of works, designed to show people the standard and to warn them that there was no alternative to grace. So the Law, the Ten Commandments, was given with grace strapped alongside it. The law brings fallen mankind under condemnation, and the grace and mercy of God expressed in the symbolism of the ceremonial law showed what Christ would do to save. The covenant of grace began to operate as soon as our first parents fell. Even in the period of the law, it was still there operating alongside the law, and offering the only viable alternative for salvation.
‘This is my blood of the New Testament which is shed for many,’ but not for everyone. How do you know if it is shed for you? You know, because you've received him. There's been a work in your heart of the Holy Spirit regenerating you, opening your eyes to see your need, and to see the meaning of the death of Christ, and with your whole heart you've received him and depended upon him, and so now you are one of the many – ‘which is shed for many.’