There are times when I wonder what exactly the Bible means when it tells us not to be anxious. I mean, where does being careful or prudent turn into being anxious?

John Piper, after almost being run over while walking across the street one day, wondered about the same thing and wrote a great article on it. Here is his conclusion:

“Do not be anxious for your life” (Luke 12:22) does not mean: Walk on red (at least not always). It means: 1) don’t fantasize nervously about getting pasted in the crosswalk; 2) believe that if you do get pasted, God is still in control and you will be with him and he will take care of your family; 3) if a carton of gold is across the street and the kingdom of God is on this side, don’t cross even on green; 4) if a red light tries to stop you from giving a big missions offering this week, walk on red! (Financial precautions are almost always too conservative.) After blue, God’s favorite color is green. Consider the lilies.

God’s Favorite Color :: Desiring God Christian Resource Library.