Salvation is not just for the church. In every age salvation is always the same way–by grace through faith. Old Testament saints were not saved by works or by keeping the law but through faith. However, they expressed that faith through their obedience to the law. But it is not the blood of bulls and goats but the blood of Christ that saves us (see Hebrews 10:1-11). God rewards the Old Testament saints on the basis of their faithfulness to him the same way we will be rewarded when we get to heaven.