While an argument can be made that all Christians should quit their "secular" jobs, sell all their possessions, and preach the gospel fulltime, I am thinking that its basis may not biblical. What then could be a biblical basis for not quitting one's job?
You seem to be alluding to the account of the rich young man in the Gospels:
And, behold, one came and said unto him, Good Master, what good thing shall I do, that I may have eternal life? And he said unto him, Why callest thou me good? there is none good but one, that is, God: but if thou wilt enter into life, keep the commandments. He saith unto him, Which? Jesus said, Thou shalt do no murder, Thou shalt not commit adultery, Thou shalt not steal, Thou shalt not bear false witness, Honour thy father and thy mother: and, Thou shalt love thy neighbour as thyself. The young man saith unto him, All these things have I kept from my youth up: what lack I yet? Jesus said unto him, If thou wilt be perfect, go and sell that thou hast, and give to the poor, and thou shalt have treasure in heaven: and come and follow me. But when the young man heard that saying, he went away sorrowful: for he had great possessions.
And when he was gone forth into the way, there came one running, and kneeled to him, and asked him, Good Master, what shall I do that I may inherit eternal life? And Jesus said unto him, Why callest thou me good? there is none good but one, that is, God. Thou knowest the commandments, Do not commit adultery, Do not kill, Do not steal, Do not bear false witness, Defraud not, Honour thy father and mother. And he answered and said unto him, Master, all these have I observed from my youth. Then Jesus beholding him loved him, and said unto him, One thing thou lackest: go thy way, sell whatsoever thou hast, and give to the poor, and thou shalt have treasure in heaven: and come, take up the cross, and follow me. And he was sad at that saying, and went away grieved: for he had great possessions.
First, in these Scriptures we note that Jesus is speaking specifically to one particular individual whose attachment to his wealth was an impediment to his faith. As the Church Fathers pointed out, although it is difficult for a rich man to enter the kingdom of heaven (Matthew 19:23), it is not impossible. Joseph of Arimathaea is an example of a rich man who was Jesus' disciple (Matthew 27:57).
Second, in the accounts of the rich young man, Christ does not urge the young man to "preach the Gospel". He is asked, rather, that he take up his cross (Mark 10:21) and follow Jesus (Matthew 19:21, Mark 10:21) - not to preach.
Throughout the New Testament, the importance of truth is emphasized. Christ is the Truth (John 14:6). Jesus taught that one must worship in Spirit and Truth (John 4:24). The Church itself is described as the pillar and foundation of truth (1 Timothy 3:15). Like Paul immediately after his conversion (see below), many may feel "inspired" to begin preaching the Gospel, without really being prepared to do so. The result is spiritual delusion, leading to heresies and schisms (1 Corinthians 11:19). The fact that there are so many Christian "denominations" (a term more suited to currency than the Church) with conflicting beliefs attests to the fact that many, many persons throughout history must have preached another Gospel (1 Galatians 1:18): When conflicting doctrine is taught by multiple sects, either all or all but one of the sects must have been teaching falsehoods.
Third, many understand that to follow Jesus means to preach the Gospel. This belief has no basis in Scripture. To follow Jesus means to obey Him (John 14:23), not to preach, unless specifically directed to do so. The famous "Great Commission" was given specifically to the eleven remaining Apostles, who alone were assembled by Jesus (Matthew 28:16), and were commanded to baptize and to teach all nations ... to observe all things whatsoever I have commanded you (Matthew 28:20). It was not a commandment that was given to all disciples or believers in general.
A close reading of the Acts of the Apostles will show that when the disciples went forth to preach, they were sent either directly by the Apostles or by one(s) who were appointed by the Apostles or by others who were successively appointed to preach. One exception was Paul, who appeared to begin preaching shortly after his conversion without being so appointed (Acts 9:20), but very quickly had to be rescued (Acts 9:25). The next time we see Paul beginning a ministry, it will be under the direct supervision of an Apostle (Barnabas; see Acts 11:25).
Yes, at least for the first two elements of quitting and selling. Let me explain. First, however, an illustrative anecdote.
Years ago I had the privilege of interacting in person with the now late author, Anglican priest, and theologian John R. W. Stott. I remember him talking about a young man who when asked what his career path was going to be replied, "I'm going into the ministry." Stott then asked him, "Oh really? What ministry?"
His--and my--point was simply this: God wants all his children to be involved in “ministry,” whether as vocational workers in a church or parachurch ministry, or as butchers, bakers, or candlestick makers. Every vocation and occupation can potentially be a ministry under God's lordship. Ministry in essence is servanthood in the service of the king. That servanthood can be expressed in myriad ways, each with the imprint of the master on it.
The Sanctity and Significance of Work
Paul through the inspiration of the Holy Spirit told the Christians in Thessaloníki,
Now we command you, brethren, in the name of our Lord Jesus Christ, that you keep away from every brother who leads an unruly life and not according to the tradition which you received from us. For you yourselves know how you ought to follow our example, because we did not act in an undisciplined manner among you, nor did we eat anyone’s bread without paying for it, but with labor and hardship we kept working night and day so that we would not be a burden to any of you; not because we do not have the right to this, but in order to offer ourselves as a model for you, so that you would follow our example. For even when we were with you, we used to give you this order: if anyone is not willing to work, then he is not to eat, either. For we hear that some among you are leading an undisciplined life, doing no work at all, but acting like busybodies. Now such persons we command and exhort in the Lord Jesus Christ to work in quiet fashion and eat their own bread. But as for you, brethren, do not grow weary of doing good (2 Thessalonians 3:6-10 NASB, my emphasis).
Some Christians are under the impression God invoked a curse on work in Genesis Chapter 3 (vss.17-19). Not so. God invoked a curse on the earth, not work. Because of Adam's disobedience, work did become more difficult than heretofore—the ol' “sweat of thy face” locution in the King James version (v.18). God did not, however, rescind his original command to Adam to “cultivate [(or tend, dress, or work)]” the garden and “keep [(or take care of, or guard)] it” (vs.15).
As you mentioned in your question, Paul set an example for his converts by working hard and providing for his own needs. As an apostle he had every right to be supported by the churches he founded, but in some instances he refused to claim that right. While in Thessaloníki, he received support from the believers in Phillipi (see Philippians 4:10-20). Evidently the Thessalonians did not have the spiritual maturity yet to realize they were accountable to and responsible for the apostle Paul and his material needs. Rather than asserting his "right" to expect support, Paul allowed God to supply his needs through a more mature group of Christians (viz., the Philippians).
A Key: A Web of Relationships
Herein is the key to understanding the importance of working to support missionaries and other vocational servants of the Lord who have been commended to a given ministry by one or more local churches:
The apostle Paul was in a web of relationships with fellow believers who recognized God's special calling on his life and to whom Paul felt an obligation to serve faithfully and in a God honoring way.
In other words, Paul was just as much accountable to them as they were accountable to him as their founding pastor. This accountability seems to be missing from the cult-like folks (or movement) of whom you speak. They may sound super spiritual; in reality, however, they seem to me to be living "unruly" (alternate reading, "undisciplined") lives (again, 2 Thessalonians 4:6 and 11 NASB), though I could possibly be wrong.
Ordination As Commendation
In conclusion, the biblical concept of commendation, as recorded in Acts Chapter 14 (see vss. 23 and 26), provides us with a biblical pattern which Christians who desire to do a work for God in the 21st century need to follow. That pattern is characterized by
involvement in a web of relationships with other Christians in one or more local churches, and/or perhaps a "sending" (i.e., missions) organization
accountability to those Christians
recognition by those Christians that God has indeed called those "preachers of the gospel" to a given work, followed by a commendation to that work and a willingness on their part to provide at least some financial support
the willingness of the commended person or persons to do bi-vocational ministry, when necessary, as did the apostle Paul, so as to set a good example for both believers, as well as potential believers.
This is a great question!
The Bible does have an obvious slant against "filthy lucre," and well it should, because it's simple (even trivial) to put the pursuit of money ahead of our faith in the Lord. But, the Bible also suggests that labor is not in itself a distraction from the path of Christ.
The story begins a long, long time ago... with Adam.
And unto Adam he said, Because thou hast hearkened unto the voice of thy wife, and hast eaten of the tree, of which I commanded thee, saying, Thou shalt not eat of it: cursed is the ground for thy sake; in sorrow shalt thou eat of it all the days of thy life; thorns also and thistles shall it bring forth to thee; and thou shalt eat the herb of the field; in the sweat of thy face shalt thou eat bread, till thou return unto the ground; for out of it wast thou taken: for dust thou art, and unto dust shalt thou return. (KJV Genesis 3:17-19, emphasis mine, as is any emphasis hereafter)
This passage suggests that God expected Adam (and, by extension, his children) to labor for their provision. The many methods of barter and exchange neither pre-empt nor abrogate this requirement. Indeed, it is difficult for me to believe that the Lord would expect people to live under the curse given to Adam without labor, though on the surface, it appears that this is true:
Go your ways: behold, I send you forth as lambs among wolves. Carry neither purse, nor scrip, nor shoes: and salute no man by the way. And into whatsoever house ye enter, first say, Peace be to this house. And if the son of peace be there, your peace shall rest upon it: if not, it shall turn to you again. And in the same house remain, eating and drinking such things as they give: for the labourer is worthy of his hire. Go not from house to house. (Luke 10:3-7)
Here the Lord is commanding His apostles to proselyte, and the expectation is that they would be blessed with people who would provide for them as they labor. This suggests that if we, too, dedicate our lives to the Lord, that we should dispense with our careers and live on the charity of those we teach and the providence of Heaven.
This appears supported by the more general command of the Lord:
Now when Jesus heard these things, he said unto him, Yet lackest thou one thing: sell all that thou hast, and distribute unto the poor, and thou shalt have treasure in heaven: and come, follow me. (Luke 18:22)
But here's where we begin to see what the Lord really intended. This one verse, quoted often to underscore the idea of living a physically impoverished life in an effort to gain greater spiritual blessings, is but a small part of a much larger story. Luke 18:18-25 is the story of the wealthy ruler asking how he can obtain eternal life. And the moral of the story is in verse 23.
And when he heard this, he was very sorrowful: for he was very rich.
Wealth isn't the problem. Jesus dealt with both the wealthy and the poor regularly. He and His apostles had their own funds with which they paid their way (John 13:29). It is assumed they were donations, but whether they were or were not is irrelevant. Money and its aquisition is not the issue — allowing the processes of obtaining it to interfere with your devotion to the Lord is.
And he said unto them, When I sent you without purse, and scrip, and shoes, lacked ye any thing? And they said, Nothing. Then said he unto them, But now, he that hath a purse, let him take it, and likewise his scrip: and he that hath no sword, let him sell his garment, and buy one. For I say unto you, that this that is written must yet be accomplished in me, And he was reckoned among the transgressors: for the things concerning me have an end. (Luke 22:35-37)
The point that following Jesus is not about leaving your career, but never allowing your career to come between you and your God is driven home in Mark 8:34-38, of which I'll only quote the first verse:
And when he had called the people unto him with his disciples also, he said unto them, Whosoever will come after me, let him deny himself, and take up his cross, and follow me.
If the whole world wonderously chose to follow Christ, and the interpretation of the Bible was that we would all leave our careers and depend on providence and charity to provide for us, who upon the Earth would be laboring to care for all the others? The curse of Adam remains until the end, when Jesus judges all and the Earth is made new (Revelation 21:1). We must labor for our bread, and it will not be held against us so long as we deny ourselves the temptation of money being a solution for anything other than providing for our bread. After all, if we don't, how do we give to the poor as we are commanded?
Let him that stole steal no more: but rather let him labour, working with his hands the thing which is good, that he may have to give to him that needeth. (Ephesians 4:28, see also Acts 20:32-35, where it appears Paul labored himself to provide for his needs rather than depend on the charity of others.)
Beyond what's been brought up already, you have keep in mind the consistent biblical emphasis on motives, not merely actions. Why you're doing something (or refusing to do something) is at least as important -- and very often more important -- than what you're doing (or refusing to do).
The easy example for this is Isaiah 29:13 & Matthew 15:8: "These people honor me with their lips, but their hearts are far from me." But see also Genesis 6:5 (God laments their motives, not just their actions). Or Matthew 16:1, 19:3, etc. where it says that Jesus' enemies asked Him questions only to test him, while Nicodemus in John 3 approached Him with a string of questions out of sincere interest and respect.
Anyway, the point is: if someone refuses to give up his job and become a vagabond preacher, why not? Is it out of sincere intentions ("I can use all this to further God's purposes")? Or is it because -- like the rich young ruler Matthew 19 -- the person puts his deep-down trust in money instead of God?
Several good scriptural references have already been provided in the other answers. I'd add to them examples like Lydia in Acts 16 (a wealthy merchant who hosted Paul's group in Thyatira) and Philemon (another rich individual who hosted fellow believers in his home). Neither of these folks gave up their wealth or their living, nor were they ever advised that they should do so. That's hard to explain if Jesus truly expected and commanded all believers to quit their jobs, sell their possessions, and go about from place to place preaching the gospel.