1 Thessalonians 3:3-5

3so that no one would be unsettled by these trials. For you know quite well that we are destined for them. 4In fact, when we were with you, we kept telling you that we would be persecuted. And it turned out that way, as you well know. 5For this reason, when I could stand it no longer, I sent to find out about your faith. I was afraid that in some way the tempter had tempted you and that our labors might have been in vain.