In 1 Cor. 9:19 Paul said that he was a voluntary slave:

¹⁹ For though I am free from all men, I have made myself a slave to all, that I might win the more.

The apostle was referring to the law in Exodus 21:5, 6, which mandates setting Hebrew slaves free at the end of six years. It says,

⁵ But if the slave plainly says, “I love my master, my wife, and my children; I will not go out as a free man,” ⁶ then his master shall bring him to God, then he shall bring him to the door or the doorpost. And his master shall pierce his ear with an awl; and he shall serve him permanently.

This shows the difference between a slave under compulsion and a voluntary slave. If a man had been sold into slavery because of a debt that he could not pay, his master was to set him free after six years (Exodus 21:2). The time of slavery was normally set in terms of “weeks” of years, and the Sabbath year was when he was to be set free.

In Paul’s case, Jesus appeared to him on the Damascus Road and redeemed him from the slave-system of Hagar (earthly Jerusalem). Paul thus became a bondslave of Jesus Christ—no doubt against his will, as it were. But bondage to Jesus is true freedom (from sin, the real slave-master). Paul soon discovered his new-found freedom, saw its benefit, and then refused to leave his new Master. He became a voluntary “bond-servant of Christ Jesus” (Rom. 1:1).

Paul’s ear had been pierced with the awl of Christ. His ear had been “opened” (Psalm 40:6), and it was his “delight” to do the will of Christ, because His law was now written in his heart (Psalm 40:8). In other words, Paul served the law of his Master, not out of compulsion, but because he was in full agreement. He said in Rom. 7:22, “I joyfully concur with the law of God in the inner man.”

This is the meaning of Paul’s statement in 1 Cor. 9:17, “For if I do this voluntarily, I have a reward.” The apostle understood the law and how it applied spiritually to himself and to all those who serve Christ joyfully and in agreement with His law.

Of course, those who have never studied the laws of God might miss the significance of Paul’s teaching.

Who is Under the Law?

Paul continues in 1 Cor. 9:20, saying,

²⁰ And to the Jews I became as a Jew, that I might win Jews; to those who are under the law, as under the Law, though not being myself under the Law, that I might win those who are under the Law.

One must have some knowledge of the law in order to understand what Paul was saying here. A great many people have misunderstood this verse. First, we must understand the term “under the Law,” for it has been misunderstood by the majority of Christians who have not studied the law.

When a man sinned, his sin was reckoned as a debt. If he stole a sheep, he owed his victim two sheep, or double restitution (Exodus 22:4). But if the thief “slaughters it or sells it, he shall pay five oxen for the ox and four sheep for the sheep” (Exodus 22:1). The debt in such a case is increased fourfold or fivefold, if the stolen item cannot be returned alive and intact.

If the thief is unable to pay restitution, then he is to be “sold for his theft” (Exodus 22:3). In other words, he must work (by compulsion) to repay his debt to the victim. The will of the law in such a case took precedence over the will of the thief. The judge did not ask the thief if he would like to volunteer for slavery. The thief had no choice in the matter, for once the debt was incurred, the will of the law ruled him.

The thief (slave) was then said to be “under the law” for as long as it took for the debt to be paid. Technically, the term should be understood to mean “under THE WILL (or decree) of the law.”

Hence, all sinners are debtors, and all debtors are “under the law” until their debt is paid. When the debt is paid, then they are “under grace,” for the law no longer has a need to impose its will upon the former debtor. The sinner is then released.

Paul says that “the law is spiritual” (Rom. 7:14). Its principles are spiritual in the end, so the law continues to have application under the New Covenant, even if some of the outward forms (listed in the book of Hebrews) have been changed. When Jesus redeemed us according to the laws of redemption, He purchased slaves from Sin, the great slave-master of humanity. Those redeemed slaves then became slaves to Jesus Christ, for the law commands redeemed slaves to serve their redeemer (Lev. 25:53).

As we have already shown by Paul’s earlier writing, Jesus has two kinds of slaves: compulsory slaves and voluntary slaves. Paul was a joyful voluntary slave and expected to receive a greater reward than those who served grudgingly or by compulsion.

With this in mind, we may understand Paul’s assertion in 1 Cor. 9:20, where the apostle contemplated winning “those who are under the Law.” He was not merely talking about Jews, for he had broadened his scope to include the whole world.

Who are under the law? Paul tells us in Rom. 3:19,

¹⁹ Now we know that whatever the Law says, it speaks to those who are under the Law, that every mouth may be closed, and all the world may become accountable to God.

Not only Jews, but the whole world is under the law until Christ’s payment for the sin of the world is applied specifically to them. Paul reinforces this by telling us a few verses later that “all have sinned” (Rom. 3:23). In other words, every sinner (debtor) is “under the law.” This includes “all the world,” and not just Jews.

Some have tried to argue that the law was given only to Israel, and so no one else could be under the law. That argument ignores the fact that a mixed multitude came out of Egypt with the children of Israel (Exodus 12:38), and that the law itself said in Num. 15:16,

¹⁶ There is to be one law and one ordinance for you and for the alien who sojourns with you.

The Kingdom of God does not allow for two different standards of righteousness. All are equally required to observe the same law.

Definitions of a Jew

Paul says in 1 Cor. 9:20, “to the Jews I became as a Jew.” Many may wonder what he was talking about, saying, “was not Paul already a Jew by birth? How, then, could he become as a Jew?”

The term “Jew” had more than one definition. Originally, it meant a physical descendant of the man named Judah. As time passed, it took on a tribal definition, regardless of genealogy, which included any wives that may have come from other tribes or from other nations. It also included any non-Israelites who may have immigrated to Israel, living within the tribal boundaries of Judah.

When the Kingdom split after the death of Solomon, “Jew” was broadened and given a nationalistic meaning that included the tribe of Benjamin and Levi. Sometimes, however, the term was given a religious definition to mean an adherent of Judaism, regardless of genealogy.

But in Rom. 2:28, 29 Paul raised a legal question as to who is and who is not truly a Jew. His point was that the adherents of Judaism, those with physical circumcision, were not Jews at all—at least, not in the sight of God. Only those with heart circumcision were Jews insofar as God’s definition was concerned. In other words, genealogy did not define the term in the divine court. It was all about the heart, because Judah means “praise,” and no one is truly praising God apart from heart circumcision via the New Covenant.

So Paul says, “his praise [i.e., status in the tribe of Judah] is not from men, but from God.”

This reveals a conflict that has persisted to this day about who has the right to call himself a Jew. The world usually applies the term to describe either a biological connection to Judah or to one who is an adherent of Judaism—that is, one that remains under the Old Covenant. But God’s viewpoint differs, and in the end his view will prevail. Those who have come under the New Covenant, with its seal of heart circumcision, regardless of their genealogy, are the real Jews by God’s definition, for only they can truly praise God in the way He expects. No one can despise Jesus Christ and expect God to accept his praise in religious meetings.

In 1 Cor. 9:20, Paul uses the term “Jew” in the sense that the world uses the term. In other words, Paul considered himself to be a true Jew through the New Covenant, but he was willing to become as the other type of Jew in order to win them to Christ. This did not mean that he must fall into their error of rejecting Jesus as the Christ, nor did it mean that he must agree that their animal sacrifices had merit after Jesus’ crucifixion.

So what did he mean?

We see hints of this first in his attempt to preach Christ in the synagogues on his missionary journeys. For example, when he went to Corinth, we read in Acts 18:4,

⁴ And he was reasoning in the synagogue every Sabbath and trying to persuade Jews and Greeks.

Note that once again Paul used the term Jew in its worldly definition. This was not the time to dispute the technicalities of semantics. But Paul went to the synagogue, dressed appropriately, and “became as a Jew” in order to win them to Christ. Later, he was constrained to go to Jerusalem for the feast of Pentecost (Acts 20:16). On his arrival, he was greeted by the church in Jerusalem (Acts 21:17) but found himself to be a controversial figure (Acts 21:20, 21).

Paul found it expedient to become as a Jew in order to accommodate the Christian believers in Jerusalem! So he paid the purification expenses of four men who had taken vows, and Paul even purified himself along with them (Acts 21:26). Were these purification rites really necessary? No, but they were important to others. So Paul “became as a Jew” as a matter of expediency, even though his own conscience told him that such actions had no merit before God. In other words, Paul followed the principle laid down in 1 Cor. 8:9, 11,

⁹ But take care lest this liberty of yours somehow become a stumbling block to the weak… ¹¹ For through your knowledge he who is weak is ruined, the brother for whose sake Christ died.

Paul’s viewpoint differed greatly with many of the Jewish believers—especially those in the Jerusalem church. But he was unwilling to insist upon his liberty if it would destroy his brothers in Christ. So whether he was in a synagogue in a Greek city or in Jerusalem itself, he “became as a Jew” as the situation required.

Likewise, he became as one “under the law” to win all those sinners to Christ. This should not be interpreted to mean that Paul became lawless. He did not participate in the sin of the world. Rather, he identified with their slavery to sin, being willing to place himself in subjection as if he were a fellow debtor. Hence, he says in 1 Cor. 9:19, "I have made myself a slave to all, that I might win the more."

His slavery was voluntary.