So first application of this is, don't be caught out. You don't know when you are going to die. It could be sooner rather than later. Neither do you know when the Lord will return and wind up this world. You better be ready. You better have repented and come to him and be walking with him.
But there's a second application. If the master of this house had known when the thief was coming, he would have made a special effort and waited and watched, but he is not going to watch all the time; that would be too much effort. He would only be up and waiting if he had some precise information. It's a very interesting little saying. The implication is that he won't wait all the time. He is not going to take that much trouble over this. There are some people who say, ‘All right, this Bible makes sense. I need God's forgiveness. I want to be sure I'm going to heaven. But I want it to be as easy as possible. Like this particular householder who will only watch if he knows the precise time, some people say, ‘What can I do to be saved? Is there something I can do, which may cost me a little, but it is within my means? God would be pleased with me for doing that good thing. It will purchase my salvation at a certain price which I can afford. I will give to charity, or purchase a park bench somewhere, or perhaps send some money to a famine relief fund. God will be pleased with me for that.’ It's rather like being ready to wait up at a precise time to protect your house against the burglar, but not being ready to wait all the time. Don't say, ‘I am interested in salvation if you are just asking me to do a few good works or patch up my life a little.’ No, you have got to have that conversion whereby your sins are forgiven. You have got to give your life to Christ so that now you are his and you love him and you walk with him. If you are converted to Christ, you are ready whenever he comes.
There is a day of account coming, and if you are unforgiven and you have never believed in Christ, then it will be too late. What did you do for him? Did you watch? Only he can provide your salvation. He came he suffered and died on Calvary's cross. He bore your eternal weight of punishment, an amazing thing to do. And because he became man he felt it just as you and I should feel it, except that it was all compressed hideously into the space of a few hours. He went through that so that our sin could be cancelled out and we could be forgiven. He has done everything necessary to save us. By his power he must change our lives and give us spiritual life. We cannot work up any of these things for ourselves.