Was salvation available prior to the “new” covenant? What did scripture mean saying Christ would “Confirm the covenant”?   Genesis and Exodus show the administration of the covenant being changed several times as Israel sins.  If leaders failed the children paid the price so Israel developed a saying; “The father’s have eaten the sour grape but the children’s teeth are on edge”.  The better promises of Hebrews 8 is that God will teach you rather than having to depend on your father or a Levite. The NT is about changing of the guardians from humans to God himself.