Charles Ellicott Commentary 2 Thessalonians 1:4

"so that we ourselves glory in you in the churches of God for your patience and faith in all your persecutions and in the afflictions which ye endure;" — 2 Thessalonians 1:4 (ASV)

So that we ourselves — Why was it less likely that St. Paul and his companions would glory in the Thessalonians, compared to other friends or even the Thessalonians themselves? Perhaps it was because praising their own converts seemed like self-praise. A much more probable reason, however, is that the writers had previously felt and expressed misgivings on this point, which aligns better with the thought in 2 Thessalonians 1:3.

Glory in you in the churches of God — This means not only giving thanks to God (which might include outbursts of praise during the public services of "the churches") but also speaking about them to others in places like Corinth. In a similar way, St. Paul "boasted" to the Thessalonians about the Corinthians (2 Corinthians 9:2).

Your patience and faith — This phrase proved that St. Paul no longer had reason for misgiving, and that the tempter’s efforts to use persecution had not made the apostles' labors to be in vain (see 1 Thessalonians 3:5). In the New Testament, "patience" does not mean meek submissiveness, but heroic endurance. The "faith" mentioned here is nearly equivalent to "hope," except that it introduces the ground of that hope—namely, confidence in the living God. It also includes the idea of faithfulness.

Persecutions and tribulations — The difference between these two words is that while "tribulation" is a general term that does not necessarily imply personal enemies, "persecution" means that a specific group of people was organizing active measures to trouble the Church. They were still "enduring" such persecution when this letter was written.