I’m assuming that no one produces the yellow pages anymore… but at one time, it was the main resource for locating goods and services. Additionally, there was also such a thing as the “Christian Yellow Pages.”
I had just moved from Africa so was unaware that this existed until walking into our office one morning to see a stack of them in the entrance hall. Upon seeing them, my first response was: “why.” Someone informed me that this enabled Christians to know who the Christian business people were in town. That seemed rather weird. As a missionary I was not accustomed to that kind of proliferation of Christianity.
My second thought was that this was indeed a good idea. It let Christians know who NOT to employ and which business to avoid. The goal of a Christian is to connect with lost people, and here was a resource that enabled you to stay away from Christian business people.
Once a Christian understands their purpose for this life, it completely changes the paradigm. You no longer look at the world the same way. We are on planet earth to evangelize, not help Christians get rich. A Great Commission Christian is always looking for opportunities to connect with lost people so why go to a Christian’s place of business?