Even from the very beginning we see the fear that persecution will affect faith. Here Paul is worried that opposition would in some way affect the church in Thessalonica, even though they knew it was coming! He is reassured when Timothy reports back on both their faith and their concern for Paul (and his companions). Paul states that he continues to pray for them, and seems to give the content of his prayers: “And may the Lord cause you to increase and abound in love for one another and for all, just as we do for you, so that your hearts are strengthened in holiness to be blameless before our God and Father at the coming of our Lord Jesus with all his saints.“
There are some warnings for us here. First, persecution is real. Even if we aren’t currently experiencing it, others are. We shouldn’t let it affect our faith. In fact, it should move us to compassion and prayer. Second, we see the reality of Satan: “for fear that the tempter somehow tempted you.” Temptation is always just around the corner. It can come from our own minds, the world around us, or through the instigation of the devil. After all, he tried to tempt Jesus too (Matthew 4:1-11)! There are many ways to keep him at bay, but the best are Bible study and prayer.