Paul references the law and the prophets hundreds of times in his epistles. This does not take away from his special ministry to preach Jesus Christ according to the revelation of the mystery (Rom 16:25).
Nevertheless, a common opposition to mid-Acts Pauline right division is in pointing out Paul’s use of other scripture.
If Paul is the preacher and teacher of a mystery kept secret since the world began, then, why does Paul quote prophecy? If we are not under the law why does he quote the law so many times? If the mystery was not revealed why does he quote from scripture already revealed?
Some would use the instances Paul quotes prophecy as evidence that he preaches the same kingdom message of Israel and the Twelve apostles, and did not receive the mystery of Christ.
This simplistic analysis is unbecoming of a workman that needeth not to be ashamed (2 Tim 2:15).
Just because the apostle of the mystery quotes prophecy sometimes does not mean everything he taught was prophesied.
There are many reasons why the apostle of the dispensation of the grace of God would quote the law and the prophets.
1. It was the only inspired scripture at that time
As the Lord started Paul’s ministry the only inspired scripture was what prophets spoke since the world began. If Paul never quoted God’s word, then that would be a good reason to doubt whether the Lord spoke to him at all. This brings us to another reason.
2. To authenticate his apostleship
If Paul had avoided using the law and prophets in his teachings then Paul would be like Muhammad or Joseph Smith starting a brand new religion. Even while teaching the mystery of Christ, Paul had to prove his apostleship did not void the prophecy of Christ (Rom 3:31).
Israel could search their scriptures to learn about their Messiah who had come in the Lord Jesus Christ. This same Jesus, the Lord Jesus of the scriptures, appeared also to Paul and revealed the mystery (Rom 1:5).
Paul’s knowledge and use of the scriptures confirmed to his kinsmen that God was not throwing Israel, their promises, and their scriptures to the trash bin of history.
3. All scripture is profitable
Mid-Acts Pauline right division does not excise non-Pauline scripture from our memory. Pauline dispensationalists are wrongly accused of only studying Paul. It is ironic, then, that within Paul’s writings we find hundreds of references to the rest of the Bible.
A steward of God’s mysteries needs to be more than acquainted with the entire Bible including the law and prophets.
It was Paul that wrote the definitive statement on the profitability and sufficiency of all scripture (2 Tim 3:16). He ends the foundational book of Romans with an appeal to all of scripture, including the prophets (Rom 16:26).
4. To reprove, rebuke, or instruct in righteousness
All scripture is profitable for a purpose. Paul writes entire epistles of rebuke and instruction in righteousness to both Jews and Gentiles. Why should he need to avoid using God inspired scripture which adequately rebukes wrong behavior, and instructs in right behavior?
The Corinthians were the sign of Paul’s apostleship according to the mystery of Christ, but after multiple references to Moses and the law, Paul says to the Corinthians:
“Now these things were our examples, to the intent we should not lust after evil things, as they also lusted.” – 1 Cor 10:6
Paul is not putting the Corinthians under the law here, but using the law to rebuke and instruct some very carnal members of the body of Christ. There are many examples of this in Paul’s ministry.
5. To communicate the gospel
The law was not given with the intent to save anyone. It was given for the knowledge of sin (Rom 3:19-20).
The law is a schoolmaster to bring us to Christ, and it would be strange if Paul did not use it lawfully to teach the mystery of the gospel (Gal 3:24; 1 Tim 1:8).
“For what saith the scripture? Abraham believed God, and it was counted unto him for righteousness.” – Romans 4:3
6. To communicate with Israel
Though Paul says clearly he is the apostle of the Gentiles, it should not be missed that he was sent to all men with the gospel of grace which included unbelieving Israel (Acts 9:15).
“And unto the Jews I became as a Jew, that I might gain the Jews… I am made all things to all men, that I might by all means save some.” – 1 Cor 9:20-22
When talking to Israel and in their synagogues he uses the scriptures of the Jews to bring them to and understanding of his doctrine.
In Acts 13 Paul is preaching to a synagogue of his kinsmen and retells Israel’s history. In Acts 17 before the Greek audience, he references their poets and philosophers in order to contrast them with the gospel of the grace of God.
Paul quotes scripture more in his epistles in which he is ministering to Israel.
7. To prove Jesus was the Christ
Without the law and the prophets there is no promise of a coming Messiah. The scriptures are evidence Jesus is the Son of God. If Jesus was not the Son of God of the scriptures, then the preaching of the cross is in vain.
Paul went to synagogues of unbelieving Jews to persuade them that Jesus was the Christ and that their Lord died for them on the cross to provide their salvation by grace.
“And when Silas and Timotheus were come from Macedonia, Paul was pressed in the spirit, and testified to the Jews that Jesus was Christ.” – Acts 18:5
From what did he testify that Jesus was Christ? From the scriptures.
8. To teach about how salvation comes to Israel (past and future)
Knowing the mystery of Christ allowed Paul to understand the mystery of God’s will for both heaven and earth (Eph 1:10). The mystery information about Christ affects more than just the church, and the manifold wisdom of God explains how God could justify sinful Israel and grant their promised inheritance.
“For the promise, that he should be the heir of the world, was not to Abraham, or to his seed, through the law, but through the righteousness of faith.” – Rom 4:13
In Romans 9-11 Paul quotes from the law and the prophets almost every other verse. For specifically in these chapters Paul makes it clear he is talking about Israel, and how God will fulfill his promise to bring them salvation (Rom 9:1-6, 10:1, 11:27).
“For this is my covenant unto them, when I shall take away their sins.” – Rom 11:27
8. To contrast another dispensation with the present
There are thousands of references to the prophets and the law on this website, yet we boldly declare our mission to make all men see the fellowship of the mystery (Eph 3:9).
As we teach the purpose God has for the church today, we often contrast it to God’s purpose for Israel by quoting prophecy. Paul did the same thing.
“Wherefore remember, that ye being in time past Gentiles in the flesh, who are called Uncircumcision by that which is called the Circumcision in the flesh made by hands…but now…” – Eph 2:11-13
“For yourselves know perfectly that the day of the Lord so cometh as a thief in the night…But ye, brethren, are not in darkness…” – 1 Thess 5:2-4
In Romans 8:36 Paul quotes prophecy concerning Israel’s suffering as sheep, and then contrasts it sharply to how the church responds to suffering:
“Nay, in all these things we are more than conquerors through him that loved us.” – Rom 8:37
These are just a few reasons for Paul to reference the law and the prophets. There are others. None of them take away from Paul’s special ministry to make all men see the fellowship of the mystery (Col 1:26, Eph 6:19).
When Paul uses other scripture (law and the prophets) in his epistles, it shows that Paul was using all scripture for the profit of all, but it was not the only thing he spoke about.
“But we speak the wisdom of God in a mystery, even the hidden wisdom, which God ordained before the world unto our glory:” – 1 Cor 2:7
It is not hard to figure out that Paul quotes the law and the prophets for the same reasons we do.
The more important question has always been why the law, the prophets, and the ministry of the twelve apostles never mention the hidden wisdom of God found exclusively in Paul’s ministry.