1 Corinthians 9:6-9

Or is it only Barnabas and I who have to work to support ourselves? What soldier has to pay his own expenses? What farmer plants a vineyard and doesn’t have the right to eat some of its fruit? What shepherd cares for a flock of sheep and isn’t allowed to drink some of the milk? Am I expressing merely a human opinion, or does the law say the same thing? For the law of Moses says, “You must not muzzle an ox to keep it from eating as it treads out the grain.” Was God thinking only about oxen when he said this?