So a third co-worker is watching him and the other christian. He has heard the other christian preach quite a bit.
He gets a chance to work side by side with the quiet man. He feels compelled to engage this man about who he is, and what his interests are. After a while the man begins to explain the joy he has in the Lord. How the Lord called him out of darkness and into the light. Preaches the gospel to him in a way that he hasn't heard or felt before. Though he has heard "the good news" before.

Andrew...
I hope you can bare with my words.
What you are saying is, that if a man preaches the gospel,whether he has the right motives or not, is the only biblical way?

Let me ask you what you think of this(btw, this is more experience than parable)

A christian man at work shows great interest in preaching the "good news" to his fellow workers. He talks about it more than he does politics, sports, current events,etc.
He also shows interest in commenting about women that walk by in a way that grieves the spirit.

Also...

We have another man at the same place of work. He is a quiet, kind man. Doesn't run his mouth a lot. Works hard. Minds his own work. Yet he has a joy that most men don't have.
There's something different about him. Something that makes people curious.

Romans 15:5-6 (kjv)

2 Peter 1:10(esv)
Therefore, brothers, be all the more diligent to make your calling and election sure, for if you practice these qualities you will never fall.

I say this because we all say "Amen".

The parable of the persistent widow should sum it up

Please read 1 Peter 4: 12-19 as well.

Iron sharpens Iron.

Almost every day, this guy throws the bait out there. Usually the first comment, which is a post designed to get reaction. And time after time people take the bait.

He has received much biblical council, true desire to see him born again.

I for one am tired of seeing people respond to it.

You can make the argument that a response is necessary for new comers and alike...

Well... it also makes people think you are judgmental and cruel to him. Because they don't see it daily like most of us.

If a child helps a dieing dog, tending to his wounds, and the dog bites him, then we can blame the dog.

Humble words I agree with. I too have been humbled by the Lord recently.