Question: The Law of Moses was a “covenant of works,” i.e., “works-based” salvation. The Apostle Paul states that “the just shall live by faith” (Romans:1:17), referencing Abraham, who preceded the law by 400 years. Isn’t this verse applied to Israel, even though we understand that they were under the law of Moses, a covenant of works? Yet, the Bible also clearly points out that “no man shall be justified by doing the works of the law” (Galatians:2:16). We see that the Law of Moses reigned over Israel for about 1,500 years until Christ’s death on the cross. If Israelites were saved by just obeying/keeping the law, this translates into works for salvation. We see that Moses gave Israel the Law, “grace and truth came only after Christ had come into the world.” (John:1:17). This passage clearly states that Israel could not be under grace if they followed the Law of Moses, because grace and truth came after Christ came to the world. Do you see a distinction between the rules of life and faith under these two covenants?
Response: You’ve quoted some very important scriptures. In Hebrews:11:30-33, we read of those who lived after the Law: “By faith the walls of Jericho fell down.... By faith the harlot Rahab perished not...when she had received the spies with peace....
[T]ime would fail me to tell of Gideon...Barak...Samson...Jephthae...David also...Samuel, and the prophets: Who through faith subdued kingdoms, wrought righteousness, obtained promises, stopped the mouths of lions.”
Some say “Jews were saved by keeping the Law.” The Scriptures disagree. As Galatians:3:11 also tells us, “No man is justified by the law in the sight of God, it is evident: for, The just shall live by faith.” Paul quotes from Habakkuk:2:4, so we can’t dismiss this as applying only to the New Testament. It is clear that “salvation by faith” apart from the Law is found in the Old Testament. Paul wrote that the purpose of the Law was to serve as a “schoolmaster [tutor] to bring us unto Christ, that we might be justified by faith” (Galatians:3:24). Paul also makes the point that “by the deeds of the law there shall no flesh be justified in his sight: for by the law is the knowledge of sin”(Romans:3:20]). The Law was never intended to be the basis of salvation. Rather, the purpose of the Law was to make us aware of our sin as part of the process to bring us to Christ.
David was also saved by faith, according to Paul (Romans:4:6-8), where he quoted Psalm:32:1-2. Other citations consistently point out that in the Old Testament salvation was through faith alone (see Romans:4:23-24). “Righteousness” is given to those exercising faith in God, including Abraham, Isaac, Jacob, David, those that followed—and us. We all partake of the same way of salvation!
As Dave Hunt noted, “Though the prophets didn’t fully understand it, Paul still calls it ‘the gospel of God, which he had promised afore by his prophets in the holy scriptures.’ One of the most powerful arguments we have for Jews or anyone is that the entire gospel—Christ’s birth, life, death, and resurrection—was foretold in detail in the Old Testament. We simply preach today what God has proclaimed in His Word for thousands of years! For those who come to Christ in faith, the Law was their tutor and “...after that faith is come, we are no longer under a schoolmaster. For ye are all the children of God by faith in Christ Jesus.” (See also Romans chapter 7 for Paul’s clarification of the Law.)