1  Jesus told his disciples: "There was a rich man whose manager was accused of wasting his possessions.
2  So he called him in and asked him, 'What is this I hear about you? Give an account of your management, because you cannot be manager any longer.'
3  "The manager said to himself, 'What shall I do now? My master is taking away my job. I'm not strong enough to dig, and I'm ashamed to beg--
4  I know what I'll do so that, when I lose my job here, people will welcome me into their houses.'
5  "So he called in each one of his master's debtors. He asked the first, 'How much do you owe my master?'
6  "'Eight hundred gallons of olive oil,' he replied. "The manager told him, 'Take your bill, sit down quickly, and make it four hundred.'
7  "Then he asked the second, 'And how much do you owe?' "'A thousand bushels of wheat,' he replied. "He told him, 'Take your bill and make it eight hundred.'
8  "The master commended the dishonest manager because he had acted shrewdly. For the people of this world are more shrewd in dealing with their own kind than are the people of the light.
9  I tell you, use worldly wealth to gain friends for yourselves, so that when it is gone, you will be welcomed into eternal dwellings.
10  "Whoever can be trusted with very little can also be trusted with much, and whoever is dishonest with very little will also be dishonest with much.
11  So if you have not been trustworthy in handling worldly wealth, who will trust you with true riches?
12  And if you have not been trustworthy with someone else's property, who will give you property of your own?
13  "No servant can serve two masters. Either he will hate the one and love the other, or he will be devoted to the one and despise the other. You cannot serve both God and Money."

1.  Why did Jesus use a corrupt business practice as an illustration?

Jesus compared the shrewdness of worldly people to that of "the people of light," as if to say that unsaved people were better at business than saved people.

He didn't condone the practices but He did say there was something to be learned here about how other people remember the way we deal with them.  The manager still got fired because of what he did.

Jesus taught to be trustworthy on small things first, then larger responsibilities will follow.

2.  We can only serve one master.  How is it different serving God instead of money or other worldly interests?

Serving God is looking for truth and doing what is right.  Serving financial interests often means rationalizing things that are untruthful or selfish.  A lot of skill can be used to rationalize an improper practice, and the skill can be admired, but the outcome of the rationalization can't be condoned or encouraged.

An example of a rationalization is:  Taking something you shouldn't from someone else, and then saying it was okay because you needed it for some higher purpose.