It is shown, in a brief digression, that the death of Christ was necessary in order that the new covenant should come into force. An eternal inheritance i.e. an enduring fellowship with God was promised long ago to God's people; and they could not obtain it under the first covenant, which afforded no real deliverance from sin. Before it could be obtained a death had to take place, so that all the sins of the past might be removed and men might start afresh under a new covenant (Hebrews 9:15). Why a death was necessary is explained by the analogy of a will or testament. The Greek word diatheke can mean either a covenant or a will, and the writer avails himself of this double meaning in order to bring out a particular aspect of the death of Christ. For a will to come into effect, the person who made it must die. This was recognised even in the case of the first covenant or will, which was ratified by the blood of a slain victim, in the solemn manner described in various OT texts (Leviticus 4:4; Numbers 19:6; Numbers 19:17 f.; Exodus 12:12). Everything connected with that first covenant, the Tabernacle and all its furniture, was likewise sprinkled with blood. It may be regarded, indeed, as a fixed principle of the Law that every act which has for its aim the forgiveness of sins must be accompanied with the shedding of blood.
Related Commentaries of Hebrews 9:15
Hebrews 9:15-21
15 And for this cause he is the mediator of the new testament, that by means of death, for the redemption of the transgressions that were under the first testament, they which are called might receive the promise of eternal inheritance.
16 For where a testament is, there must also of necessity bee the death of the testator.
17 For a testament is of force after men are dead: otherwise it is of no strength at all while the testator liveth.
18 Whereupon neither the first testament was dedicatedf without blood.
19 For when Moses had spoken every precept to all the people according to the law, he took the blood of calves and of goats, with water, and scarletg wool, and hyssop, and sprinkled both the book, and all the people,
20 Saying, This is the blood of the testament which God hath enjoined unto you.
21 Moreover he sprinkled with blood both the tabernacle, and all the vessels of the ministry.