1 Timothy 5:17–18
Let the elders that rule well be counted worthy of double honour, especially they who labour in the word and doctrine.
For the scripture saith, Thou shalt not muzzle the ox that treadeth out the corn. And, The labourer is worthy of his reward.
Paul now turns to those who lead the church. Not every elder receives the same emphasis here. He is speaking especially of those who spend their lives working in the Word and teaching sound doctrine.
And Paul says something very plain: they are to be counted worthy of double honor.
Part of that honor certainly includes respect and appreciation. But Paul makes it clear he is also talking about practical support. Those who give their lives to teaching the Word should not have to worry about whether they will be able to provide for their families.
To make the point, Paul reaches back into the Old Testament.
When an ox was grinding grain, the law said you were not to muzzle it. The animal doing the work was allowed to eat from the grain it was helping produce. It would be cruel to let the ox labor all day while preventing it from receiving any benefit from the work.
The same idea applies to ministry.
Those who spend their days studying the Scriptures, praying, preparing, and teaching are helping feed the people of God. And just like the ox in the field, they should not be left hungry while doing the work.
Jesus Himself said the same thing when He sent His disciples out to minister. The laborer, He said, is worthy of his reward.
It is a simple principle really. When someone faithfully spends his life feeding others with the Word, the church should make sure he is cared for as well.

