"The disciples were amazed at his words. But Jesus said again,'Children, how hard it is to enter the kingdom of God! It is easier for a camel to go through the eye of a needle than for someone who is rich to enter the kingdom of God.'”
"And Jesus went into the temple of God, and cast out all of them who sold and bought in the temple, and overthrew the tables of the moneychangers, and the seats of them that sold doves, And said unto them, It is written, My house shall be called the house of prayer; but ye have made it a den of thieves."
Matthew 21: 12-13
"When you give a luncheon or a dinner, do not invite your friends or your brothers or your relatives or rich neighbors, lest they also invite you in return, and repayment come to you. But when you give a reception, invite the poor, the crippled, the lame, the blind, and you will be blessed, since they do not have the means to repay you; for you will be repaid at the resurrection of the righteous."
"If there is a poor man among you, one of your brothers, in any of the towns of the land which the LORD your God is giving you, you shall not harden your heart, nor close your hand to your poor brother; but you shall freely open your hand to him, and generously lend him sufficient for his need in whatever he lacks."
So what's the incentive for a christian to become rich? If he does, he'll have to share his money with the poor and then he'll go to hell anyways. While some Christians want to end the separation of church and state, Jesus makes it pretty clear that he doesn't want any sort of capitalist practices in his church.
A few bible passages don't fully explain Christianity, there are many Christians organizations who interpret the bible and instruct the faithful. In 325 christian leaders met in Nicaea to discuss theological issues, they prohibited usury (lending money at interest) among the clergy. In 1311 Pope Clement V banned usury and declared all legislation which allowed for usury invalid. It wasn't until the Protestant Reformation that certain christian churches began to allow for usury, but even in 1776 the secular free market enthusiast Adam Smith advocated an interest rate ceiling, limiting the profitability of loaning banks. If a rich christian wants to avoid hell, he can give his money away or loan it, at no interest. But loans are essential to a growing economy, if money can't be loaned then the rich have little incentive to lend it.
The Parable of the talents is clearly applicable to economics. In it, a master travels far away but entrusts his servants with talents (large amounts of money) while he's gone. When he returns, the servant who he gave five talents has used the money to make another five talents, the servant he gave two talents has made another two talents, but the servant who was only given one talent hasn't made any money at all. So the master confiscates his talent, gives it to the servant with ten talents, banishes the third servant and says:
"For to everyone who has will be given, and he will have abundance, but from him who doesn't have, even that which he has will be taken away"
This parable isn't straightforward to interpret, religious scholars don't all agree about what it means. The master gives money to his servants, he doesn't charge interest but the servant whom doesn't invest the money has his money given to the servant who does. Perhaps Jesus told it to encourage people with money to spend it on productive ventures. Banishing a servant simply because he returns the money you gave him and doesn't double it like the other servants have seems unfair. If lending money at interest is wrong, then why should you expect interest when you give somebody a gift? Perhaps Jesus told the story as an example of why a rich man is unlikely to go into heaven, he completely avoids his responsibility to the poor. Or perhaps the lesson isn't moral, but practical, the rich become richer, the strong become stronger and the powerful become more powerful, this is just a fact of life. Whatever the message, of all the bible passages listed, this is the most pro-capitalist. The master in the story rewards the servants who spend and punish those who save which sounds like demand supply economics (not the supply side economics Ronald Reagan favored). Yet it advocates taking from the poor to give to the rich, which is not something that most secular proponents of capitalism believe in.
So why do christians support a system that gives a disproportionately large share of money to the top 1%? There's the cynical explanation that the church is in cahoots with the rich and spreads information to keep the poor poor. It is hard for a poor person to become rich if he follows christian morality. First, he can't get a loan. Second, he has an obligation to help the poor. Third, his money can be taken away from him and given to the rich. On the other hand, it's pretty easy for a rich person to stay rich, or even become richer, according to the parable of the talents he should be given wealth, even if he does nothing to earn it. The middle class (like the second servant in the parable), get a decent deal under christian morality.
Maybe christians are in favor of capitalism because it is the opposite of communism, an economic system which demands the destruction of religion. In a communistic system, the state helps the poor and there are no rich. In most capitalist systems, there are a few rich (and if the parable of talents is followed, much of their wealth comes from the poor) who will probably go to hell. But christianity doesn't decry middle class people or small business owners, so the people between poor and rich can lead good lives, and they are encouraged to make the lives of the poorest better. If you believe in heaven, the christian system is similar to reincarnation. The rich who enjoy life on earth the most are reincarnated in hell. People who don't manage to acquire massive sums of wealth and give what little they have to those poorer than themselves are reincarnated in heaven.