Don't Muzzle an Ox while it is threshing?

Reading through the letter to Timothy by the Apostle Paul today I came across this verse which I have heard many times before but never really understood the meaning of it:

The elders who direct the affairs of the church well are worthy of double honor, especially those whose work is preaching and teaching. For Scripture says, “Do not muzzle an ox while it is treading out the grain,” and “The worker deserves his wages.” (1 Timothy 5:17-18)

Paul (who also quotes this in 1 Corinthians 9:9) is once again using a farming metaphor to teach us a spiritual truth. I wrote about "Don't kick against the goads" previously. In that story Paul was recounting his first encounter with Jesus (Acts 26:14) during which he learned that resisting God's guidance in life would only end up injuring ourselves. He compared himself to a stubborn ox. Here in this lesson to Timothy (or rather a lesson for Timothy to instruct his church congregation) he is comparing the elders to oxen (plural of ox!) doing the work of God. Church elders who direct the affairs of the church and especially those who have the jobs of preaching and teaching, are to be treated not only with "double honour", but supported financially as well. He quoted from Deuteronomy 25:4 where Moses was instructing the Israelites God's rules for right living. The verse comes strangely right in the middle of other instructions that seem totally unrelated to it. The original idea of putting a muzzle on an oz during the process of tramping the grain on the threshing floor is that it cannot eat the grain. God through Moses is saying that this is wrong. But the reason is not specified. Based on this excellent blog in thegospelcoalition.org Justin Taylor explained that the original meaning in Deuteronomy is likely this:

"By process of elimination, this leaves us with the situation of a man borrowing or renting an ox to thresh his own grain. In that event, his self-interest would entail preserving as much of his threshed grain as possible; on the other hand, he would have no intrinsic motivation to let the ox eat of his grain. If the animal ended up in a weakened state or unhealthy as a result, the situation does not result in any economic loss on his end. This, then, seems like the most plausible situation for requiring a command. The covenant stipulation works against the selfish motive for a man to take advantage of another man’s property. (To use a modern analogy, at the risk of anachronism, this is the reason that rental stores today have agreements about returning rented equipment in good working order; they know that when someone doesn’t own something there is an increased propensity for recklessness and lack of diligent care.)"... 
"Seen in this light, v. 4 fits the original context quite well. Otherwise the verse is an anomaly which seems to stand out."

So to apply it to Paul's use in the New Testament, he explains:
"Once this is seen, rich texture is added to Paul’s use of this verse. His point is not really that the Corinthians should have compassion or mercy for him and Barnabas, but that this is a matter of fundamental justice. The issue is not really kindness, but rights. When Paul says this is not really about the oxen, he is pointing to this wider and deeper reality at play in this verse as it was originally to be understood. Therefore the Corinthians should want to provide appropriate compensation as an expression of justice, even if Paul ultimately rejects the offer."

So what have I learned from this. Firstly, my attitude towards the scripture (especially the Old Testament) must be that of reverence. There is always a deeper truth than what my finite mind can muster. I must take a serious attitude to learn. Secondly, when I meet someone who is doing the work of God full time, pay special respect. Take a serious interest in learning about his work. Do not come with a negative attitude that the person is only interested in financial support but offer it joyfully. God wants me to know that this person has a right to what God has generously entrusted to me.