The author compares two situations, one less severe and one more severe (see study note on Hebrews 9:14). The less severe situation is the old punishment of death for someone who refused to follow the law of Moses (see Deuteronomy 13:6–11). The more severe situation involves those who reject Christ and show him disrespect.
How much more severely do you think one deserves to be punished: Eternal damnation awaits those who have rejected Christ.
The blood of the covenant, which made us holy, is Christ’s perfect sacrifice (9:11–10:18).
insulted the Spirit of grace: Those who reject the Spirit’s guidance and mercy deny the truth of the good news and the greatness of Christ and his saving work (compare Mark 3:22–30).