From the TeachingtheWord Bible Knowledgebase

The Old and New Testaments both clearly teach that all who are saved, throughout all history, are saved by grace alone, through faith alone, in Christ alone. But some in both the Dispensationalist and Reformed camps deny that Old Testament saints were saved in this way.

Hyper-Dispensationalists' Legalism

Some people mistakenly believe that only New Testament believers are saved by grace, and that Old Testament believers were saved by their obedience to the law or by some other means. Extreme Dispensationalists of the 20th century such as C. R. Stam and J. C. O'Hair held the view that law-keeping saved in the Old Testament. But the Apostle Paul makes the impossibility of salvation through law-keeping abundantly clear in his letter to the Galatians, in which he repeatedly quotes the Old Testament law as proof. Here is a key passage:

For as many as are of the works of the law are under the curse; for it is written, "Cursed is everyone who does not continue in all things which are written in the book of the law, to do them." But that no one is justified by the law in the sight of God is evident, for "the just shall live by faith." Yet the law is not of faith, but "the man who does them shall live by them." Christ has redeemed us from the curse of the law, having become a curse for us (for it is written, "Cursed is everyone who hangs on a tree"), that the blessing of Abraham might come upon the Gentiles in Christ Jesus, that we might receive the promise of the Spirit through faith. (Galatians 3:10-14)

Redemptive-Historical Theology's Flawed View of Christ

In the Reformed camp, Dr. Richard Gaffin, the leading proponent of the postmodern Biblical Theology movement (also known as redemptive-historical theology), says that it would be "redemptive-historically anachronistic to say that an old covenant believer like Abraham or David" was "united with Christ, because the Christ who is in view, and union with Christ, is specifically the exalted Christ, the redemptive-historical Christ if you will, the Christ who is what He is now by virtue of His death and resurrection, and He did not exist in the situation of Abraham or David."¹

Gaffin and other Biblical Theology advocates are simply wrong. Here Gaffin reveals one of the fatal flaws of the redemptive-historical movement's theology: its doctrine of the person and work of Jesus Christ. Union of Old Testament saints with Christ is not "anachronistic". Jesus said, "Before Abraham was, I AM" (John 8:58). He is the Word from the beginning (John 1:1). His "goings forth are from of old, from everlasting" (Micah 5:2). The Israelites "drank of that spiritual Rock that followed them, and that Rock was Christ" (1 Corinthians 10:4).

The New Testament's Commentary on the Old

Believers need to keep in mind that the Bible is one Book, given by one Divine Author; although God's revelation of truth is progressive, it is a unified body of truth, without contradiction. We need also to keep in mind that the New Testament is the Holy Spirit's own commentary on the Old. He does not leave us in the realm of doubt or speculation about the way Old Testament saints were saved, and He leaves no doubt that salvation is now, always has been, and always will be, by grace through faith in Christ alone.

Under the inspiration of the Holy Spirit, the New Testament writers teach this great truth by using the Old Testament Scriptures themselves. The Apostle Paul spends the first three chapters of Romans proving that both Jew and Gentile are under God's condemnation by quoting extensively from the Old Testament. He then concludes by saying that no one will be declared righteous by observing the law (Rom. 3:20). He then points to Abraham, the father of Hebrews who lived centuries before Moses, as proof that salvation comes through faith in Christ apart from works (Romans 4:1-25; cf. Genesis 15:6, Galatians 3:6-9).

The Meaning of the Old Testament Sacrifices: Faith in Christ

Paul's epistles, the book of Hebrews, and other New Testament Scriptures make it plain that Jesus Christ is the fulfillment of all the Old Testament types, symbols and prophecies (Luke 24:44, Romans 3:21-22, the entire book of Hebrews). The book of Hebrews (11:4) testifies that even Abel the son of Adam (Genesis 4) was justified by faith. The inspired writer bases this declaration not on any merit of Abel's, but on the fact that Abel trusted in the coming Redeemer whose blood was prefigured by that of the sacrifice he offered - the sacrifice prescribed by God. The Scriptures make it plain that the Old Testament saints offered their sacrifices for sin in anticipation of the prophesied Holy One who would come and make full and final atonement:

Your father Abraham rejoiced to see My day, and he saw it and was glad. (John 8:56)

These all died in faith, not having received the promises, but having seen them afar off were assured of them, embraced them and confessed that they were strangers and pilgrims on the earth. (Hebrews 11:13)

And all these, having obtained a good testimony through faith, did not receive the promise, God having provided something better for us, that they should not be made perfect apart from us. (Hebrews 11:39-40)

But now in Christ Jesus you who once were far off have been brought near by the blood of Christ. For He Himself is our peace, who has made both one, and has broken down the middle wall of separation, having abolished in His flesh the enmity, that is, the law of commandments contained in ordinances, so as to create in Himself one new man from the two, thus making peace, and that He might reconcile them both to God in one body through the cross, thereby putting to death the enmity. And He came and preached peace to you who were afar off and to those who were near.

For through Him we both have access by one Spirit to the Father. Now, therefore, you are no longer strangers and foreigners, but fellow citizens with the saints and members of the household of God, having been built on the foundation of the apostles and prophets, Jesus Christ Himself being the chief cornerstone, in whom the whole building, being fitted together, grows into a holy temple in the Lord, in whom you also are being built together for a dwelling place of God in the Spirit. (Ephesians 2:13-22)

One Savior, One Hope

New Testament saints look back with thanksgiving to Christ's atonement for our sins on the cross (Hebrews 13:20-21), just as Old Testament saints looked forward in hopeful anticipation of His propitiation for their sins (Isaiah 53) - and all look forward to the day when Christ shall come again.

Job, one of the oldest of the Old Testament saints, testified:

For I know that my Redeemer lives, and He shall stand at last on the earth; and after my skin is destroyed, this I know, that in my flesh I shall see God, whom I shall see for myself, and my eyes shall behold, and not another. How my heart yearns within me!

Jude gave this same assurance to New Testament saints:

Now to Him who is able to keep you from stumbling, and to present you faultless before the presence of His glory with exceeding joy, to God our Savior, Who alone is wise, be glory and majesty, dominion and power, both now and forever. Amen. (Jude 24-25)

References:

1. Lecture by Richard B. Gaffin at the Auburn Avenue Pastors Conference 2005, transcript of Session 13, response to the fourth question from the audience.

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