The letter to the Hebrews primarily addressed Christians from a Jewish background. Like us, they needed to understand how the Gospel relates to the Old Testament. Only Jesus fulfills the requirements of the law, and he does so in all who hear and believe Him (Heb 10:14; cf Mt 5:17-19). By contrast, the law of Moses condemns and curses all who transgressed it. For a time, the old covenant was the best there was to teach salvation by faith in God’s promise. But after the new covenant has arrived and eclipsed the old, the old has come to its end (cf 2Cor 3:9-11).
Therefore, whoever returns to live under the Law of Moses thereby proves that they don’t believe even Moses. By siding with those who rejected Messiah, they crucify him ‘again’ (Heb 6:6, a verse easily misunderstood when taken out of context). For whoever so despises grace and the way of living by faith deserves even more severe punishment than those who only transgressed the Law (Heb 10:28-31, 10:38).
Hebrews calls its explanation of the Old Testament and its relationship to the Gospel “solid food”, without which we cannot become skilled in “the word of righteousness” to distinguish good from evil (Heb 5:12-14). Thus, no less than 12 long chapters in Hebrews are devoted to this doctrine of faith before only a single final chapter on Christian virtue. For without such doctrine, we would be bound to mistake Jesus for merely another instructor in self improvement, instead of looking to him as the author and perfecter of our faith (Heb 12:1-2).
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