There are people in this world who feel themselves to be so wise, so self-confident, so able to live and to get through life, that they have no time for these defences which the Lord has provided: salvation, having sins forgiven, having the guidance and the blessing of God. We see the foolishness of human self-confidence. How can we get through life, with all its twists and turns, with the enemy of souls at work? How can we get through life cut off from God and without him, and without his blessing, and his help? That is the implicit illustration. Keep them in view; keep sound wisdom and discretion. Discretion means forethought, and planning, and bearing in mind the future, anticipating trouble. That is the trouble with us before we come to Christ we do not anticipate trouble in this world, we are so foolish, we are so ignorant, we think it is a great world. I am going to make my fortune, I am going to do well; nothing can actually harm me, or get the better of me. We are so blind, we do not see this as a spiritual battle with the enemy seeking to pollute us and bring us down to hell, and ruin us and pervert us through life's journey. We are just blind to the reality of the situation, and we have no plans. But the believer is somebody who has been given shrewdness and discretion. He knows this is a fallen world, he knows you cannot rely on human nature, he knows the truth of God and the purposes of God are all that matter. And so he plans in the light of that.