I believe it was Paul that said, “We are written epistles of God, read of all men.” When you're on the street, and when you're at your work, and wherever you are, somebody is watching you.           
And especially after you have said and made your confession that you are a Christian, they'll watch you much closer then, and that gives an influence to—to the people that's around about you. And we should watch what we do. Because, if we produce the wrong influence, then we bring reproach, not so much upon ourselves, but upon what we claim to be: Christians. We bring it upon Christ. And no one, if we would think, you would never want to bring reproach upon Christ. But the wrong act, at the wrong time, will certainly cause a wrong reflection towards the person that's watching you. And everybody is watched, when you profess to be a Christian.