This is such an apt illustration of what it is to begin to follow Christ without conversion. What happens at conversion is that a person is shown by the Spirit of God all that will be involved in following Christ. That does not mean that he has the full experience of the Christian life in advance, but it does mean that he has some conception of what is coming. There will not be experiences in the Christian life which take him completely by surprise. He knows that he must part with sin permanently and completely in order to come to Christ. At conversion he was baptised into Christ Jesus, and that means he was baptised into his death; he has joined with Christ in dying to sin, and having been through that spiritual experience, it is not some totally new experience to have to fight against residual sin. In the language of the parable, he will not run out of materials or fail to have enough money to pay for the building to be completed, because there were full costings done at the start of the Christian life. The Christian life ends at death, or at the return of Christ. The struggle against sin must continue until then.
It does not come as a shock to the believer to learn that he must love God, more even that he loves his own natural family. If his family does not come to Christ, it does not come as shock to learn that they are opposed to Christian discipleship, and what they value most is in this world, and any worship they engage in is limited to outward forms only. It does not come as a shock to learn that the world persecutes the church, and the Christian must take up his cross daily in order to follow Christ. It does not come as a surprise to learn that Christ requires us to walk in humility and to conform our lives to his commandments. It does not come as a shock to find that when we witness to a lost world, the world largely rejects the message.
But others see the tower as an attempt to live, not the Christian life, but the non-Christian life, the life away from God. They see it as a warning of what will happen if we try to live without God. It is as if the builder has failed to ask the question, ‘Can I do this without God?’ He hasn’t sat down and counted the cost of living for this world. Is it even possible in this world of constant disappointments and letdowns and upheavals? What am I building? Something grand for myself? Have I really thought about my life plan? Without God, you won’t get very far. ‘Lest happily after he hath laid the foundation’ – in the illustration he doesn't get very far, he has put the footings in, and dug out the ground, and – in modern terms – laid foundation concrete in trenches. He is ready now for the walls. And at that point, he runs out of funds. High aims in life, but all kinds of things are going to go wrong. Sometimes your career path doesn't go as you imagined it would. You're not appreciated as you feel you should have been. Perhaps you are badly treated. This is an unfair world. Or it may be relationships that go wrong: family, husband, wife. Maybe it's your fault; maybe it isn't. Perhaps it's something else entirely different hinders you. Maybe you are sadly rather ill , or perhaps there is a tragedy. Perhaps you rake in the money, but something happens inside you, and suddenly it no longer makes you happy. So many things can frustrate life when we are away from God.
The shame which this miniature parable speaks of comes either way. It comes to those who build a life without God, and it comes to those who try to live the Christian life without having properly considered the cost. It is the shame due to those who have begun something which they are not able to complete, because they did not consider carefully enough what was involved.