Look here, when we say, “Today or tomorrow we are going to teach a certain topic and learn all about it. We will run a small group and make the Lord known.” How do we know what the life of people will be like tomorrow? Their faith is like a fire—it burns brightly a little while, then dies downs, then brightly again. What we ought to say is, “If the Lord wants to, He will use us to reveal Himself to them.”
Otherwise we are boasting about our own plans, and all such boasting is evil.