John Chrysostom

"But we, being taken from you for a short time in presence, not in heart, endeavored the more abundantly to see your face with great desire." He has not said "separated," but what was much more. He had spoken above of flattery, showing that he did not flatter, that he did not seek glory. He speaks here concerning love. Because he had said above, "as a father his children," "as a nurse," here he uses another expression, "being made orphans," which is said of children who have lost their fathers. And yet they were made orphans. …

Homily on 1 Thessalonians 3 ↗

Theophylact of Ohrid

Here the apostle speaks of love. Above he said: "as a father his children" (v. 11) and: "as a nurse" (v. 7), and here "being separated" (in the Slavonic text – "having been orphaned"), which is characteristic of children seeking their parents. This is so that we might understand from this how strongly he loved them. But at the same time he also hints at the sorrow in which he found himself on account of the separation. …

Commentary on 1 Thessalonians ↗

Thomas Aquinas

Then when Paul says, but since we were bereft of you, brethren, for a short time, he shows the remedy that he proposed to apply for them, namely, that he will personally go to them. In regard to this he makes three points: first, he discusses his proposed visit; secondly he treats the obstacle to his visit (2:18); thirdly, he gives the reason why he wanted to go (2:19). …

Commentary on 1 Thessalonians ↗