Laymen sometimes think they need not be theologians. That, however, is a very great mistake. They do need to be theologians; at least, they should be amateur theologians. In fact, that is the one vocation every man is obliged to follow. A layman does not need to be a plumber, a carpenter, a lawyer, a doctor, a teacher, a laborer, a housewife. These are all possibilities, not necessities. A layman may be one of these or the other as he chooses. But he must be a theologian. This is not an option with him but a requirement… A lay theologian is a person who has a true knowledge of God which he understands in nontechnical, nonprofessional, nonacademic terms… Is it not clear why a layman must necessarily be a theologian? Is there anyone, layman or otherwise, who does not need to know God? Does the Scripture not say, “This is life eternal, that they might know thee the only true God, and Jesus Christ, whom thou has sent” (John 17:3)? It is, then, no mere option with a layman whether he will be a theologian or not, whether he will have eternal life or not; it is no option with him whether he will know God or not. The knowledge of God is necessary to eternal life. And if eternal life is necessary for every man, then theology is also necessary for every man.
John Gerstner