Capitalism is based on the recognition of man's right to live for his own sake - to be the beneficiary of his own actions.
Jesus was the most extreme example of altruism you would ever see, the exact opposite of self-interest: He sacrificed his life so that sinners may live. The message it sends is "The moral is to live for others".
Every political system is based on ethics. Capitalism is based on rational-self interest. Socialism, communism and fascism are based on altruism, which is the message of Christianity.
Socialism is justified on the grounds of the moral duty of one man to care for another. Capitalism is based on the idea that a man lives primarily for himself, and that he is moral in pursuing HIS life and HIS happiness.
Let us not forget what was going on during the dark ages and what kind of actions were justified by the church.
This is because the message of the bible is inconclusive. One can mold it to whatever fits one's goals.
It is not a coincidence that 5 Rabies reading the bible cannot agree on the interpretation of a single paragraph. It's not that some of them are wrong and one is right - it is that the bible is inherently unclear in meaning and can be interpreted one way or another.
The real defense of Capitalism is reality-based. Facts-based.
We start by looking at the requirements of life for an individual man, the principles and values required for him to live and be happy (which is a successful state of living).
We recognize that man must act to bring and create the things he requires to survive and enjoy his life.
Capitalism is the system that allows a man, every individual, to be free to pursue his life and happiness as would be on a desert island: productivity uninterrupted by other men.
It is only by allowing every individual man this basic requirement for life that a political system actually serves man's life.
One cannot start by asking what is good for a group of people. Such question only makes sense if the intent is to talk about what is good for every individual man in the group. But then that reduces the question back to what is good for a single man.
One cannot claim, that by stealing from one man and giving it to another in the group that one is serving the "good of the group". Why is the good of the group the good of one man, but not of the other?
Yet the good of the "group" is the standard most use to judge political systems.
The only defense of Capitalism that "works" - because it is the real basis for Capitalism, is reality; rational ethics recognizing the requirements of life of a single human being.
Look at reality, not at the "word of god".