Luke 16:1-13...
From my own literal understnading, is Christ encouraging us to be dubious at times or what. Plz help me explain it.

Jesus said to his disciples, “There was once a rich man who had a servant who managed his property. The rich man was told that the manager was wasting his master's money, 2 so he called him in and said, ‘What is this I hear about you? Turn in a complete account of your handling of my property, because you cannot be my manager any longer.’ 3 The servant said to himself, ‘My master is going to dismiss me from my job. What shall I do? I am not strong enough to dig ditches, and I am ashamed to beg. 4 Now I know what I will do! Then when my job is gone, I shall have friends who will welcome me in their homes.’ 5 So he called in all the people who were in debt to his master. He asked the first one, ‘How much do you owe my master?’ 6 ‘One hundred barrels of olive oil,’ he answered. ‘Here is your account,’ the manager told him; ‘sit down and write fifty.’ 7 Then he asked another one, ‘And you—how much do you owe?’ ‘A thousand bushels of wheat,’ he answered. ‘Here is your account,’ the manager told him; ‘write eight hundred.’ 8 As a result the master of this dishonest manager praised him for doing such a shrewd thing; because the people of this world are much more shrewd in handling their affairs than the people who belong to the light.”

9 And Jesus went on to say, “And so I tell you: make friends for yourselves with worldly wealth, so that when it gives out, you will be welcomed in the eternal home. 10 Whoever is faithful in small matters will be faithful in large ones; whoever is dishonest in small matters will be dishonest in large ones. 11 If, then, you have not been faithful in handling worldly wealth, how can you be trusted with true wealth? 12 And if you have not been faithful with what belongs to someone else, who will give you what belongs to you?

13 “No servant can be the slave of two masters; such a slave will hate one and love the other or will be loyal to one and despise the other. You cannot serve both God and money.”

Jesus was not encouraging men to be dubious.
He was not commending the act of the dubious servant but his policy.It was the shrewdness and perseverance behind his act in other to secure his future that Jesus wanted believers to learn from.

The steward used his shrewdness to secure his earthly resources and the future.Jesus wants believers to exercise such shrewdness and perseverance to secure their eternal future.He also expects believers to manage their earthly resources well.Christians are often striving in spiritual pursuits but are often not doing well in the management of their finances and material possessions.
From verse 11,you will see His attention on that.

As thorpido stated, the emphasis of the parable is not the fact that the servant is dishonest 'cos the bible already called him that. The emphasis or lesson is the fact that instead of his usual way of using the perishable (money) to buy the perishable (things for himself to enjot) he learnt how to use the perishable (money) to purchase the imperishable (relathionships).

What Jesus was illustrating is that the lowest use of money is to buy things while the highest use is to transform lifes. The reward of the fomer is instant gratification whilw the reward for the latter is will entend even till eternity.