A Christian missionary who once persecuted the church More urges the letter’s audience to remember that he, Silvanus, and The companion on Paul's later journeys for whom two pastoral epistles are named More have always been gentle and concerned for the Thessalonians’ well-being.
Paul goes out of his way to mention, repeatedly (see also 1:5), that he and his companions have always acted with integrity among the Thessalonians. He is careful to note that they were neither bossy, manipulative, nor greedy when they were previously in Thessalonica. This kind of rhetoric was relatively familiar in Greek philosophical discourse. From other literature during the period, it is clear that people were wary of traveling charlatans and others who sought financial rewards for their teachings. Most teachers worth their salt were expected to back up their ideas with humility and virtue. When Paul mentions his conduct during a previous visit, he is not defending himself from opposition as much as he is reminding his audience that he is serious and not motivated by a desire to provide easy answers. The Thessalonians can count on him to speak the truth and be committed to their best interests.
When Paul describes himself, Silvanus, and Timothy as being gentle with the Thessalonians “like a nurse tenderly caring for her own children,” he characterizes their ministry as self-giving care. Paul evokes the honored image of a wet nurse, usually an enslaved woman who was lactating and charged with nourishing and caring for someone else’s young children—children either of her owners or of other enslaved individuals. Some ancient authors described wet nurses as models of honor because of the obviously self-giving aspect of their responsibility. Paul’s point here is that if a wet nurse is gentle and a source of generous nourishment for someone else’s infant, imagine how much more so she is when caring for her own child. That’s the kind of attitude Paul claims in his approach to the Thessalonians.