In the last section, Paul spoke about marital status, as he does in the final part of the chapter, but here he takes one of his little asides. In doing so, he also clarifies some of his meaning in 7:8-16. The theme of 7:17-24 is ‘don’t change your status’.
7:17-20 If a man was circumcised when he was called (when he became a Christian) he should not become uncircumcised; considering the impossibility of that in the first century, we can safely infer that Paul is speaking metaphorically here. So, if a Jewish person becomes a Christian, they remain a Jew. If a Gentile (uncircumcised) person becomes a Christian, they do not become Jews. This was an issue that Paul dealt with a number of times in his writings, and his comments here are quite consistent with all of the others; I doubt this is terribly confusing to anyone reading this in the 21st century. The next part, however, might strike some as a little more difficult…
7:21-24 If a person was a slave when they became a Christian, they remain a slave. If a person was free when they became a Christian, they must remain free. The exception is that if a person who is a slave can obtain their freedom, then that would be a good thing to do. Most of us today know about slavery from history, but not all are familiar with a form of slavery that came to be called ‘Indentured servitude”. An indentured servant was a person who sold themselves into slavery for a certain period of time to satisfy a debt, and indeed thousands of people in the 17th and 18th centuries sold themselves into indentured servitude to escape the oppression of England and pay for the crossing of the Atlantic to get to America.
In ancient Rome, people sold themselves into slavery to pay debts, or to feed their children. A person who had a past due account could be taken to court and put into slavery to satisfy their debt. If such people started fleeing their lawful (in those days) masters because they became Christians, that would have had a disastrous effect on the Gospel, and since our priority must always be on making disciples of all Nations, Paul gave the instructions that we see here.
At the same time, his advice to people who are not slaves means that they need to handle their financial affairs very carefully, lest they find themselves in bondage to more than one Master.
With this set of priorities in better focus, some of Paul’s comments in the last section are easier to follow, particularly those concerning separation and divorce. Consider this: If a person’s accepting Jesus Christ began to cause divorces all over town, how long would it be before the cause of Christ found itself on the wrong side of a moral crisis? That would surely damage the cause of Christ and bring the Gospel into disrepute− thus Paul’s advice.
Now that we have a better feel for the context in this chapter, you can see why this letter is so tricky. If we took Paul’s comments in verse 10 that a wife must not separate from her husband, and applied that instruction to a woman in the 21st century who was being regularly beaten up by her drunk husband, you would not only be doing a grave injustice, you would be engaged in false teaching, for the instruction was being given in a vastly different context in a vastly different set of circumstances that existed in c. 55 AD. Sadly, such false teaching has been going on for centuries, and it needs to stop.