Paul does mention giving “double honor” to elders, and especially those that work hard at preaching and teaching. I am in favor of giving honor and double honor to godly elders who shepherd, mentor and teach the churches. But I have a hard time interpreting “double honor” as a full-time salary and benefits. We have come up with the word “honorarium” based on this expression in the New Testament. When we present a speaker with a financial token of appreciation I actually think we are closer to Paul’s intent in this passage.
To be fair, Paul does refer to a “worker worthy of his wages” which is a quote from the Old Testament, mentioned by Jesus as well. It is probably in reference to paying for a day’s hire rather than a yearly salary. We should definitely be generous in sharing all good things with those who teach us (Gal. 6:6), but the goal is always the strengthening of the church, not the sapping of her strength. I also think we are rather limited and uncreative if we think that money is the only thing that we should give to those who teach us well.
I think that the principle of the New Testament is to release the servant to be able to fulfill a specific need in the church. I also think that the precedent is that the servant will have already been performing the service before the honor is given, rather than becoming a condition of service in advance.