Like a standard NT epistle, we open with the authors. It’s represented as coming from Paul, Timothy and Silvanus (Silas) and generally uses “we” instead of “I” throughout the letter. That said, the language is pretty consistent with other letters Paul has written so he’s likely the primary author.
As Paul and the bros pray for the Thessalonican church, they retell the cool stuff that has gone on tied to the faith of this church. They know God was working to reach this group of folks by how the good news demonstrated itself to them through Paul and the bros, not just through word but also in some ways through clear demonstrations of power, presence of the Holy Spirit and how it all impacted those who witnessed this good news. And, Paul et al. obviously conducted themselves with integrity and as good examples for the sake of the Thessalonican church (because what you do matters and influences how people hear your words. Still applies today.)
v.6 hits a favorite theme of mine as the Thessalonians followed them as they followed Christ. We should be careful when we attempt humility by cutting our opportunity off as only proclaimers in word of the good news when Paul seems to think it’s completely acceptable to have people trying to imitate him and the bros. Paul, elsewhere, will proclaim himself the chief of all sinners, however that doesn’t stop him from being comfortable with people imitating him as he pursues Jesus (and as they both try to imitate Jesus). And it’s working, the Thessalonicans took that example and have influenced people in the rest of Macedonia and in Achaia and are reaching even beyond that. Other places the bros go are telling stories about the Thessalonican church.
And it sounds like their story is an interesting one, involving turning from idols (implied false and dead) to serve the living and true God and to wait for his Son from heaven who will deliver us from the wrath to come. This wait thing is important as we’ll see later in the letter that the Thessalonicans may be getting a wee impatient and worried about the yet-to-return Jesus.