For Christ's sake - in Christ (δια Χριστόν - ἐν Χριστῷ)
We apostles are fools in the world's eyes on account of (διὰ) Christ, because we know and preach nothing but Christ: You are wise in Christ, as Christians, making your Christianity a means to your worldly greatness - union with Christ the basis of worldly wisdom. “Wise men are ye in your connection with Christ! Sagacious, enlightened Christians!” (Meyer).
Honorable (ἔνδοξοι)
With a suggestion of display and splendor. Right honorable are ye!