John Gill Commentary 1 Corinthians 9:3

"My defence to them that examine me is this." — 1 Corinthians 9:3 (ASV)

My answer to them who examine me is this . ] These words are referred by some to the following, as if the apostle's answer consisted of putting the questions he does in the next verses; but they rather seem to belong to the preceding, and the meaning to be this, that when any persons called in question his apostleship, and examined him on that point, what he chose to say in answer to them, and in defence of himself, was by referring them to the famous church at Corinth,

who were as particular persons, and as a church, his work in the Lord, and everyone of them as so many seals of his apostleship; he being the first preacher of the Gospel to them, the founder of them as a church, and the instrument of their conversion.