Hebrews 7:22

22This makes Jesus the guarantor of aa better covenant.

Hebrews 9:15-20

15Therefore he is bthe mediator of a new covenant, so that cthose who are called may dreceive the promised eternal inheritance, esince a death has occurred that redeems them from the transgressions committed under the first covenant.
The Greek word means both  covenant and will; also verses 16, 17
16For where a will is involved, the death of the one who made it must be established. 17For ga will takes effect only at death, since it is not in force as long as the one who made it is alive. 18Therefore not even the first covenant was inaugurated hwithout blood. 19For when every commandment of the law had been declared by Moses to all the people, he took ithe blood of calves and goats, jwith water and scarlet wool and hyssop, and sprinkled both the book itself and all the people, 20saying, kThis is the blood of the covenant that God commanded for you.”
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