Paul, a Jew by birth, only alludes to his father and mother in his writings (Galatians 1:15, 2Corinthians 11:22). Although the apostle does not list the names of these close relatives, who resided in Tarsus, we do know they were from the Israelite tribe of Benjamin (Philippians 3:5).
We have Luke, the author of the book of Acts, to thank for directly referencing two close relatives of Paul. They were the apostle's sister and her son (Acts 23:16). Paul's young nephew, who likely lived in Jerusalem, played a critical role in thwarting a concerted death threat against his uncle in 58 A.D. (Acts 23:12 - 22)!
How one of Paul's relatives discovered a secret plot against his life remains a mystery. What is known, however, is that the conspiracy involved forty plus Jews, bound by an oath to neither eat or drink, until they had killed him (Acts 23:12 - 15). Once discovered, the nephew told Paul of the plot, who then had him tell the Romans. Taking the threat seriously, the Romans transported the apostle out of Jerusalem with a contingent of 470 soldiers (verse 23)!
In the last chapter of Romans Paul calls one woman and five men his kinsmen (Romans 16:7, 11 and 21). The Greek word from which we get "kinsmen" in this chapter is suggenes (Strong's #G4773). It primary meaning is to convey a person has a blood relative connection with someone else (Strong's Concordance, Thayer's Greek Definitions). Its secondary, and wider, meaning is to convey a connection based on a much bigger group (e.g. Jews, Israelites, etc.). Which meaning is intended in Romans 16?
Paul uses the Greek word suggenes in only one other place in all his writings. In Romans 9, he clearly intends the word convey its widest meaning. In lamenting the gospel's rejection by Jews he states, ". . . it is a great grief to me and an unceasing sorrow in my heart, causing me even to wish myself to be accursed from Christ for my brethren, my kinsmen (suggenes) according to the flesh" (Romans 9:2 - 3, HBFV). Should the wider meaning of suggenes be applied "kinsmen" in the last chapter of Romans?
Justification of meaning
The primary, albeit narrower, meaning of kinsmen, that of a blood relative, should be used for Romans 16. This last chapter of Apostle Paul's book focuses on the unique connections he has to individuals (thirty-five total!) whom he names and not to his relationship to them as a whole. The context of the chapter, a fundamental rule of Bible study, favors using the narrower meaning of suggenes.
Second, Paul's selective use of suggenes shows he intended to convey the narrower meaning of the word, that of a relative, as opposed to its wider secondary definition. He states in Romans 16 that he has a kinsman (suggenes) relationship with only six of thirty-five people listed. Additionally, although he labels these six Jewish converts kinsmen, he does not call other Jews in the chapter his kinsmen (Priscilla, Aquila and Timothy, verses 3 - 4, 21).
The word suggenes, found four times in the apostle's writings, is utilized an additional eight times in other New Testament books (Mark 6:4, Luke 1:36, 58, 2:44, 14:12, 21:16, John 18:26 and Acts 10:24). Although a less weighty proof than what is stated above, these eight uses, all of which clearly refer to a blood relative relationship, shows the word's primary definition is more frequently intended than its secondary one.
Lastly, well-known reference works, as well as many (if not most) Biblical commentaries agree that Paul is mentioning the names of some distant relatives in Romans 16:7, 11 and 21. The Life and Epistles of Paul by Conybeare and Howson, as well as commentaries authored by Albert Barnes, John Gill, Bullinger, Henry, MacArthur and others, agree that suggenes' primary meaning should be used.
Although Paul only alludes to his parents, his fellow evangelist Luke writes of two other family members - the apostle's sister and her son.
In the closing chapter of Romans Paul sends his greetings from Corinth to distant relatives Andronicus, Herodion and Junia (a woman) living in Rome (Romans 16:7, 11). He also conveys a general greeting to those in the Empire's capital from relatives Lucius, Jason and Sosipater, all of whom are with him in Corinth (verse 21). Altogether, the New Testament acknowledges four close, and six distant, family relationships Apostle Paul enjoyed.