The man's life proved three things: that he couldn't be trusted; that he served money more than God; and that his work ethic/character was greatly lacking. In spite of all that, Jesus praised the dishonest manager for his shrewdness; for his ability to think ahead; and for his ability to create a plan of survival.
So what gives us this desperate hunger and thirst for God? Fasting is not popular, but it shows that we are serious about being closer to Him. James 4:8 promises, "Draw near to God and He will draw near to you.