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Death is necessary to validate the new covenant. The author has made it clear that Christ’s death has instituted a better covenant (vv. 11–15) which is superior to animal offerings (vv. 12–14). But the need for such a sacrifice has yet to be explored. So a key word in this section (v.16-28) is “necessary” (anankē, vv. 16, 23). In the process of exploring this point, the author clearly underscored the measureless superiority of the sacrificial death of Christ.
The New Covenant provides two gifts to a believer: redemption and inheritance. Believers receive redemption from the sins committed under the Law. In other words, Christ paid the price to free us from our own sin. His death substitutes for our death, the penalty for our sins. Like the Israelites, believers receive an inheritance, but our inheritance is eternal. By imitating the faith and patience of Abraham, believers are assured that they will inherit the marvelous promises God has made. The Mosaic covenant was ratified by blood, that is to say, death. It was not the death of the one making the covenant, but the death of the animals offered as a sacrifice to God.