2 Corinthians 12:14; 2 Corinthians 13:3

14 Behold, the third time I am ready to come to you; and I will not be burdensome to you: for I seek not yours, but you: for the children ought not to lay up for the parents, but the parents for the children.

3 Since ye seek a proof of Christ speaking in me, which to you-ward is not weak, but is mighty in you.