A: Of course, we know that Timothy was not Paul’s “natural son” because we see in (Acts 16:1) that Timothy’s father was not a Jew and Paul was a Jew (Acts 21:39)(Acts 22:3). In addition, Paul clearly stated that he was single (1 Cor 7:7-8) (although some believe Paul may have been married at one time (See: Q: #47).
This being said, there are two explanations given. The primary one, given by most, is that Paul led Timothy to saving faith in Christ. In doing this, Paul became like a “spiritual father” to Timothy. Timothy was, in essence, like Paul’s son, and Paul felt responsible for him and taught him. (I think this is often the case when someone leads another person to the Lord.)
In addition, Timothy is not the only one Paul calls his “son.” He also calls Onesimus his “son” in (Phm 1:10) “I beseech thee for my son Onesimus, whom I have begotten in my bonds.” This seems to make it much more clear that Paul called Onesimus his “son” because he had led him to the Lord while “in bonds” (in prison). Paul also calls Titus his “son” in (Titus 1:4).
(1 Cor 4:14-15) is another place that seems to bolster this viewpoint. Paul says, “I write not these things to shame you, but as my beloved sons I warn you. (15) For though ye have ten thousand instructors in Christ, yet have ye not many fathers: for in Christ Jesus I have begotten you (became your father) through the gospel.
However, there are also some who believe that Paul may have called Timothy his “son” simply because he was kind of like an “apprentice” to Paul. Paul appears to have been quite a bit older than Timothy (1 Tim 4:12), and probably was more spiritually mature as well (at least early on), so Paul was like his mentor. (Phil 2:19-24) seems to bear this out a little. Also, (Acts 16:1-3) seems to make it clear that Paul first met Timothy at Lystra. At this first meeting, Timothy is called a “disciple.” Since Paul had never met Timothy before this, and Timothy was already called a “disciple” (an indication he was already a Christian), it seems unlikely that Paul had led him to the Lord. Instead, his Godly mother Eunice or his grandmother Lois (See: 2 Tim 1:5) probably led him when he was younger.
I should also add that (1 Tim 1:2) is not the only place that Paul calls Timothy his “son.” He also does this in (1 Tim 1:18)(2 Tim 1:2)(2 Tim 2:1)(1 Cor 4:17). It is worth noting that in each of these instances, as well as the other places Paul calls someone his “son,” he uses the Greek word “teknon” rather than the much more commonly used word for “son” in the New Testament “huios.” It appears that “teknon” is often used in a more figurative sense than “huios.”
Ultimately, we cannot know for sure why Paul used the word “son,” but we know that when he used it, he had great affection for that person.
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