1 Corinthians 9:7-9

9:7 Who ever serves in the army at his own expense? Who plants a vineyard and does not eat its fruit? Who tends a flock and does not consume its milk? 9:8 Am I saying these things only on the basis of common sense, or does the law not say this as well? 9:9 For it is written in the law of Moses, “Do not muzzle an ox while it is treading out the grain.” God is not concerned here about oxen, is he?