John Calvin Commentary 1 Corinthians 9:11

"If we sowed unto you spiritual things, is it a great matter if we shall reap your carnal things?" — 1 Corinthians 9:11 (ASV)

If we have sown unto you spiritual things. There was one objection remaining—for it might be argued that labors connected with this life should undoubtedly have food and clothing as their reward, and that plowing and threshing yield fruit, of which those who labor in these things are partakers. But it is otherwise with the gospel, because its fruit is spiritual; hence, the minister of the Word, if he were to receive fruit corresponding to his labor, ought to demand nothing that is carnal.

Therefore, to prevent anyone from objecting in this manner, he argues from the greater to the less: “Though food and clothing are not of the same nature as a minister’s labors, what injury do you sustain, if you recompense what is inestimable with a thing that is small and contemptible? For in proportion to the superiority of the soul over the body, does the word of the Lord excel outward sustenance, inasmuch as it is the food of the soul.”