"Some proclaim Christ from envy and strife, but others from goodwill.  These proclaim Christ out of love, knowing that I have been put here for the defense of the gospel; the others proclaim Christ out of selfish ambition, not sincerely, but intending to increase my suffering in my imprisonment.  What does it matter?  Just this, that Christ is proclaimed in every way, whether out of false motives or true; and in that I rejoice.  I will continue to rejoice."

When Paul spent time in Philippi during his second missionary journey (Acts 16), he encountered a young woman who was proclaiming Christ in the streets.  This woman was a fortune teller.  She was proclaiming with wrong motives.  Paul cast out a demon in her, and caused trouble for all who wanted profit from the exploitation of a helpless young woman.

Here we see another allusion to this envious proclamation.

Paul is letting us know that God works all things out for His glory.  Thus, the pleasure of serving a mighty God.  But we should also be aware of this enemy walking amongst us.  Why?  We are called to be fruit inspectors. 

There are times when evil bears its claws in the midst of what we think is right.  The Christian is not supposed to revel in what is good - we are to search for what is Godly.  Sometimes there is no difference, true.  If there is a difference, what choice should we make?