Wisdom is better than weapons of war: but one sinner destroyeth much good. (Ecclesiastes 9:18)
There is a tremendous influence exerted by the life of one individual. And the influence is more potent when it is in the wrong direction. History bears this out. Adam sinned and his sin has affected the entire race of mankind. Achan sinned, and because of him an entire nation went down in defeat. Rehoboam's sin split the kingdom of Israel. The sin of Ananias and Sapphira brought the first defect into the early church, and from that day on the church has not been as potent as it was in the beginning.
You and I have an influence, either for good or for bad. No matter who you are, you occupy a place of influence. "For none of us liveth to himself, and no man dieth to himself" (Romans 14:7). My friend, all of us are preachers. You are preaching to those around you by the life that you live. I personally believe that the do-gooder, the man who boasts of his moral life apart from God is the greatest detriment. He actually stands in the way; he blocks the way to God because his message is, "Live like I do. I live without God. I just do good." There is nothing quite as deadening as that.
You are a preacher, whoever you are. It may be in a very small circle, but you are affecting someone. You are a preacher in your own home. This reminds me of a father who kept a jug of whiskey hidden in the corn crib. It was his habit to go out there every morning and get himself a drink. On a snowy morning he went out to the barn as was his habit, but this time he heard someone behind him. He turned around and found that it was his little son following him, stepping in the footsteps in the snow where his father had walked. The father asked, "What are you doing, son?" The boy answered, "I'm following in your footsteps." He sent the boy back into the house, and then he went out to the corn crib and smashed that jug of whiskey. He realized that he didn't want his boy to be following in his footsteps. Someone in your home is following in your footsteps. Where are you leading him?
You may be influencing a wide circle of human society. You may have influence in your neighborhood and in your community. You have influence in your Sunday school. Somebody is looking at you and watching to see whether or not you mean business with God. Does your going to church mean anything more to you than going to a drive-in to pick up a hamburger? Does your life suggest that there is a heaven to gain and a hell to shun? You have influence.
You remember that Peter preached a mighty sermon on the Day of Pentecost. Andrew just sat on the sidelines and could say, "That is my brother. I brought him to Christ." That was Andrew's influence. You, today, are pointing men to heaven or to hell. Now, if you want to go to hell, that's your business, but you have no right to lead a little boy there. You have no right to lead your family and those who surround you there. Even if you want to go, it's awful to lead others. Influence — "One sinner destroyeth much good." Think about it.
—From Edited Messages on Ecclesiastes by Dr. J. Vernon McGee