1 Timothy 5:18
16 If a believing woman has widows in her family, let her help them. The church should not be burdened so that it may help the widows who are truly in need. 17 Elders who provide effective leadership must be counted worthy of double honor, especially those who work hard in speaking and teaching. 18 For the scripture says, “Do not muzzle an ox while it is treading out the grain,” and, “The worker deserves his pay.” 19 Do not accept an accusation against an elder unless it can be confirmed by two or three witnesses. 20 Those guilty of sin must be rebuked before all, as a warning to the rest. 21 Before God and Christ Jesus and the elect angels, I solemnly charge you to carry out these commands without prejudice or favoritism of any kind.
Bava Metzia 91bBabylonian Talmud
The mishna teaches that Rabbi Yosei, son of Rabbi Yehuda, says: A laborer may not eat unless he performs labor with his hands and with his feet. The Gemara asks: What is the reasoning of Rabbi Yosei, son of Rabbi Yehuda? The Gemara explains: This halakha is like that of a threshing ox; just as one is not required to let an ox feed unless it is performing labor with its hands and with its feet, as it uses all four of its legs to thresh, so too a laborer is not entitled to eat unless he is performing labor with his hands and with his feet.
Notes and References
"... In 1 Corinthians 9 Paul has occasion to defend the right of an apostle to receive material support from the church in which he is working. After a series of arguments (including the bold application to the matter in hand of Deuteronomy 25:4, "Thou shalt not muzzle an ox when it is treading out the grain") he clinches the matter with a direct appeal to the authority of Jesus. (Philo, On the Special Laws, I 260; The Rabbis preferred to maintain the literal meaning - as did Josephus Antiquities of the Jews IV, 8.21 - but were prepared to argue a fortiori from oxen to men) 'In the same way the Lord commanded that those who proclaim the gospel should get their living by the gospel'. Direct allusions to the teaching of Jesus are rare in Paul's letters. To what precise saying is he referring? It is unlikely that Jesus left instructions about the maintenance of preachers in local churches. We can hardly doubt that what Paul had in mind was some fairly general saying of Jesus which could be made to fit the present case. The workman is worthy of his hire" would do very well ..."
Harvey, A. E. "The Workman is Worthy of His Hire" Fortunes of a Proverb in the Early Chuch (pp. 209-211) Brill, 1982