A.T. Robertson Commentary 1 Corinthians 9:8

"Do I speak these things after the manner of men? or saith not the law also the same?" — 1 Corinthians 9:8 (ASV)

Do I speak these things after the manner of men? (Μη κατα ανθρωπον ταυτα λαλω; ). Negative answer expected. Paul uses κατα ανθρωπον six times (1 Corinthians 3:3; 1 Corinthians 9:8; 1 Corinthians 15:32; Galatians 1:11; Galatians 3:15; Romans 3:5). The illustrations from human life are pertinent, but he has some of a higher order, from Scripture.

The law also (κα ο νομος). Perhaps objection was made that the Scripture does not support the practice of paying preachers. That objection is still made by the stingy.