1 Thessalonians 3:1-2, 5

Therefore, when we could no longer endure it, we thought it best to be left behind, alone at Athens, and we sent Timothy, our brother and God’s fellow worker in the gospel of Christ, to strengthen and encourage you for the benefit of your faith

For this reason, when I could no longer endure it, I also sent to find out about your faith, for fear that the tempter might have tempted you, and our labor would be for nothing.