1 Corinthians 9:9-11

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? 9:10 Or is he not surely speaking for our benefit? It was written for us, because the one plowing and threshing ought to work in hope of enjoying the harvest. 9:11 If we sowed spiritual blessings among you, is it too much to reap material things from you?

1 Corinthians 9:14

9:14 In the same way the Lord commanded those who proclaim the gospel to receive their living by the gospel.