1Corinthians 9:9-15 For it is written in the law of Moses, Thou shall not muzzle the mouth of the ox that treads out the corn. Does God take care for oxen? Or said he it altogether for our sakes? For our sakes, no doubt, this is written: that he that plows should plow in hope; and that he that threshes in hope should be partaker of his hope. If we have sown unto you spiritual things, is it a great thing if we shall reap your carnal things? If others be partakers of this power over you, are not we rather? Nevertheless we have not used this power; but suffer all things, lest we should hinder the gospel of Christ. Do you not know that they which minister about holy things live of the things of the temple? and they which wait at the altar are partakers with the altar? Even so has the Lord ordained that they which preach the gospel should live of the gospel. But I have used none of these things: neither have I written these things, that it should be so done unto me: for it were better for me to die, than that any man should make my glorying void. 

‘Thou shall not muzzle the mouth of the ox that treads out the corn.’ Quoted from Deuteronomy 25:4. In other kinds of labour, the oxen were often muzzled. Paul used this law to encourage supporting ministers of the gospel.

‘Treads out the corn’ Threshing was sometimes done by instruments (Isa. 28:27-28), and sometimes by oxen or other animals treading on the grain on the threshing floor. Such is still common in some places in the East.

‘That he that plows should plow in hope; and that he that threshes in hope should be partaker of his hope.’ That everyone should be a partaker of his own labours (9:7-11).

‘Spiritual things’ [Greek: pneumatikos] non-carnal; religious; or spiritual. Twelve spiritual things: Man who follows the things of the Holy Spirit (2:15; 3:1; 14:37; Gal. 6:1; Hos. 9:7). Gifts of the Spirit (Rom. 1:11; 1Cor. 1:7; 12:1; 14:1, 12). Things (Rom. 15:27; 1Cor. 2:13; 9:11). Body (resurrected, 1Cor. 15:44-46). Blessings of the Spirit (Eph. 1:3). Songs (religious, Eph. 5:19). Wisdom and knowledge (Col. 1:9). House (spiritual people, 1Pet. 2:5). Sacrifices (1Pet. 2:5). Law, because it typified the spiritual thing of the New Testament (Rom. 7:14). Meat and drink, typifying Christ the Spiritual Rock of 1Corinthians 10:3-4. Wickedness, because it is of evil spirit origin (Eph. 2:2; 6:12; John 8:44).

‘Nevertheless we have not used this power; but suffer all things, lest we should hinder the gospel of Christ.’ This is Paul’s explanation why he supported himself at Corinth. He supported himself partly by working while starting the Thessalonians’ congregation and partly through help from Philippi (2Thess. 3:7-9). Imagine being a partaker of all that Paul has sown through his work for God in the lives of the congregations where he laboured as well as being the author of no less than 14 books of the New Testament (Romans to Hebrew). ‘They which minister about holy things live of the things of the temple? and they which wait at the altar are partakers with the altar.’ The officers of the temple had a right to support when they gave their time in the temple service. They were two classes: those who ministered in holy things and those who waited on the altar. This was ordained by God, and so it is ordained by God that gospel ministers should be supported by those who receive the gospel (9:11-15; Gal. 6:6; Heb. 7:1-11; Luke 10:7; Matt. 10:10).