Yes, I also ask you loyal yokefellow (σύζυγος), “Help these women who struggled beside me in the Gospel." (Phil 4:3)
Commentaries on Philippians mention, as a matter of course, that Clement of Alexandria took the "loyal yokefellow" of Phil 4:3 as a reference to Paul's wife. To find out where Clement says this, you apparently have to go back to the 19th century (e.g., J.B. Lightfoot and Eadie), when NT scholars thought it was worth reading the church fathers. (BDAG also includes the references.) As usual, going ad fontes, repays the effort:
Clement of Alexandria (d. 215) discussed Paul's "yokefellow" in book 3 of his Stromateis, but--unless you read Latin--you can't find the passage in Schaff, the most widely-available English edition of the Ante-Nicene Fathers, because Clement's description of the sexual practices of heretics didn't pass T&T Clark's Victorian-era censors. Thanks to Henry Chadwick, there is a modern English translation, which has been made available online here. Here is the relevant psassage:
Even Paul did not hesitate in one letter to address his consort (σύζυγον). The only reason why he did not take her about with him was that it would have been an inconvenience for his ministry. Accordingly he says in a letter: 'Have we not a right to take about with us a wife that is a sister like the other apostles?' But the latter, in accordance with their particular ministry, devoted themselves to preaching without any distraction,and took their wives with them not as women with whom they had marriage relations, but as sisters, that they might be their fellow-ministers in dealing with housewives. It was through them that the Lord's teaching penetrated also the women's quarters without any scandal being aroused. We also know the directions about women deacons which are given by the noble Paul in his second letter to Timothy. Furthermore, the selfsame man cried aloud that "the kingdom of God does not consist in food and drink," not indeed in abstinence from wine and meat, "but in righteousness, peace, and joy in the Holy Spirit."(The passage was not as clear as I expected until I checked the Greek and found that the word Chadwick translates as "consort" is the same word, σύζυγος, that is translated as "companion" or "yokefellow" in Phil 4:3.)
When we look at the context, we find that Clement refers to Paul's wife in order to argue--against the followers of Basilides, who rejected marriage altogether--that marriage (and sexual relations within marriage) is okay. Like the clean and unclean food of Romans 14, marriage, for Clement, is an adiaphora.
Clement's younger contemporary, Origen (d. 253/4), had rather different reasons for mentioning Paul's wife.Origen's commentary on Romans 1:1 seems to suggest that slavery to Christ excludes the possibility of sexual relations:
Paul, then, if certain traditions are true, was called while in possession of a wife, concerning whom he speaks when writing to the Philippians, “I ask you also, my loyal mate, help these women.” Since he had become free by mutual consent with her, he calls himself a slave of Christ. But if, as others think, he had no wife, nonetheless he who was free when he was called is yet a slave of Christ. In fact what does it mean to be a slave of Christ? It means that one is a slave of the Word of God, of wisdom, righteousness, truth, and of absolutely all the virtues which are identical with Christ himself. - Origen, Romans 1.1.3 (trans Schenk p. 62)Origen returns to Paul's marital status in his commentary on Romans 4:
In order that we might remove such objections in a fitting way let us shift the explanation of [Abraham’s] dead body to say that Abraham was not dead with the infirmity of old age but in accordance with that power which the saints have at work, first of all, in themselves, and which they also admonish others to possess by saying, “Put to death your members which are earthly!” For I consider it to be absurd that we should fail to believe that this good which Paul possessed in himself—seeing that [Paul] would not command to others what he himself did not do this good which Paul possessed, I say, Abraham did not possess, so great a patriarch that the Apostle even calls him his own father. In [Abraham] as well, then, there was this mortification of the members. He was not enticed by luxury; he did not burn with lust like those of whom Paul says, “It is better to marry than to burn.” This same good was also in Sarah; and therefore it is written about her, “womanish things had ceased to function in Sarah.” For in her there was none of that feminine lasciviousness or the dissoluteness of incontinence, nor were either of them carried off unwillingly into the enjoyment of lustful desires. 4.6.7 (Schenk p. 271):Here we learn that Abraham and Sarah couldn't have children because they had advanced to such a degree of godliness that they had lost all sexual desire. They had succeeded in putting their bodies to death, as Paul instructs the Romans to do in chapter 6. Paul, says Origen, would not have exhorted the Romans to such a state of sanctity, if he did not possess it himself.
Truly the world has changed.