Under the new covenent “Not under the Law” we are saved by God’s Grace. Under the old covenent “Old Testment” “Under the law” how were God’s people saved?

It had to be by a blood offering of animals and sacrifice on the altar.

Jesus became the law and the fulfillment and the substation for the blood of animals.

Hebrews 9:11-15 But Christ being come a high priest of good things to come, by a greater and more perfect tabernacle, not made with hands, that is to say, not of this building; Neither by the blood of goats and calves, but by his own blood he entered in once into the holy place, having obtained eternal redemption for us. For if the blood of bulls and of goats, and the ashes of a heifer sprinkling the unclean, sanctifies to the purifying of the flesh: How much more shall the blood of Christ, who through the eternal Spirit offered himself without spot to God, purge your conscience from dead works to serve the living God? And for this cause he is the mediator of the new covenant, that by means of death, for the redemption of the transgressions that were under the first covenant, they who are called might receive the promise of eternal inheritance.