2 Even though I may not be an apostle to others, surely I am to you! For you are the seal of my apostleship in the Lord.

Read 1 Corinthians 9:2 Using Other Translations

If I be not an apostle unto others, yet doubtless I am to you: for the seal of mine apostleship are ye in the Lord.
If to others I am not an apostle, at least I am to you, for you are the seal of my apostleship in the Lord.
Even if others think I am not an apostle, I certainly am to you. You yourselves are proof that I am the Lord’s apostle.