All humans are "imagers" of God. Ambassadors to the world for good or ill. But missionaries are a different thing entirely. More on reddit.com

Paul made an extensive case for the right of apostles to get their living by the gospel: Am I not free? Am I not an apostle? Have I not seen Jesus our Lord? Are not you my workmanship in the Lord? If to others I am not an apostle, at least I am to you, for you are the seal of my apostleship in the Lord. This is my defense to those who would examine me. Do we not have the right to eat and drink? Do we not have the right to take along a believing wife, as do the other apostles and the brothers of the Lord and Cephas? Or is it only Barnabas and I who have no right to refrain from working for a living? Who serves as a soldier at his own expense? Who plants a vineyard without eating any of its fruit? Or who tends a flock without getting some of the milk? Do I say these things on human authority? Does not the Law say the same? For it is written in the Law of Moses, “You shall not muzzle an ox when it treads out the grain.” Is it for oxen that God is concerned? Does he not speak certainly for our sake? It was written for our sake, because the plowman should plow in hope and the thresher thresh in hope of sharing in the crop. If we have sown spiritual things among you, is it too much if we reap material things from you? If others share this rightful claim on you, do not we even more? Nevertheless, we have not made use of this right, but we endure anything rather than put an obstacle in the way of the gospel of Christ. Do you not know that those who are employed in the temple service get their food from the temple, and those who serve at the altar share in the sacrificial offerings? In the same way, the Lord commanded that those who proclaim the gospel should get their living by the gospel. But I have made no use of any of these rights, nor am I writing these things to secure any such provision. For I would rather die than have anyone deprive me of my ground for boasting. For if I preach the gospel, that gives me no ground for boasting. For necessity is laid upon me. Woe to me if I do not preach the gospel! For if I do this of my own will, I have a reward, but if not of my own will, I am still entrusted with a stewardship. What then is my reward? That in my preaching I may present the gospel free of charge, so as not to make full use of my right in the gospel. (1 Corinthians 9:1-18 ESV) (emphasis mine) The word apostle means, "one sent." They were sent away from thier homes with this instruction: And he said to them, “Go into all the world and proclaim the gospel to the whole creation. (Mark 16:15 ESV) Being travellers, it is reasonable to expect them to be granted the right to receive the necessities of life from those to whom they served the gospel. As it would be unreasonable to expect them to earn a living in foreign lands, among foreign people, while proclaiming the gospel. In my opinion anyone who fulfils the role of an apostle has the right to support from those being taught, but the primary defining characteristic of an apostle is that they are transient proclaimers of the gospel. Paul stayed long enough to get a local group up and running, and then moved on. He did stay in Ephesus for three years, but during that stay he was able to use the hall of Tyrannus to proclaim the gospel to all of Asia. The right to earn a living from the gospel is unique to apostles. Paul gave a reason for his not using his right, to support, in the text quoted above, but Paul had another reason given here: Now we command you, brothers, in the name of our Lord Jesus Christ, that you keep away from any brother who is walking in idleness and not in accord with the tradition that you received from us. For you yourselves know how you ought to imitate us, because we were not idle when we were with you, nor did we eat anyone’s bread without paying for it, but with toil and labor we worked night and day, that we might not be a burden to any of you. It was not because we do not have that right, but to give you in ourselves an example to imitate. For even when we were with you, we would give you this command: If anyone is not willing to work, let him not eat. For we hear that some among you walk in idleness, not busy at work, but busybodies. Now such persons we command and encourage in the Lord Jesus Christ to do their work quietly and to earn their own living. (2 Thessalonians 3:6-12 ESV) (emphasis mine) Everyone in the congregation of a local church is to earn their own living, this includes the elders, shepherds, of that congregation. Apostles were the only exception given by Paul. As for already established congregations supporting apostles, some did do so, but it was completely voluntary. Paul even referred to it as robbery, to emphasize the fact that it was an obligation of those who were being evangelized, not an obligation of some other congregation: I robbed other churches by accepting support from them in order to serve you. (2 Corinthians 11:8 ESV) If you feel that you are filling the role of an apostle, but those you are evangelizing do not have the means to provide food, shelter, and any other of your needs, then it seems perfectly reasonable to me that you would ask other believers, who do have excess, to help provide for your necessities of life. Keeping in mind that they are under no obligation to do so. You would likely have to convince them of the merit of supporting what you are doing. More on reddit.com