1 Thessalonians 3:3-5

3so that none of you would be shaken by these trials. For you know that we are destined for this. 4Indeed, when we were with you, we kept warning you that we would suffer persecution; and as you know, it has come to pass. 5For this reason, when I could bear it no longer, I sent to find out about your faith, for fear that the tempter had somehow tempted you and that our labor might have been in vain.