MLJ on Otherworldliness

These descriptions (the Beatitudes), I suggest, indicate clearly (perhaps more clearly than anything else in the entire realm of Scripture) the essential, utter difference between the Christian and the non-Christian. This is the thing that should really concern us; and that is why I say it is most of what a man does; the real point is this difference between the Christian and the non-Christian. The New Testament regards that as something absolutely basic and fundamental; and, as I see things at the present time, the first need in the Church is a clear understanding of this essential difference. It has become blurred; the world has come into the Church and the Church has become worldly. The line is not as distinct as it was. There were times when the distinction was clear-cut, and those have always been the greatest eras in the history of the Church. We know, however, the arguments that have been put forward. We have been told that we have to make the Church attractive to the man outside, and the idea is to become as much like him as we can. There were certain popular padres (ministers) during the First World War who mixed with their men, and smoked with them and did this, that, and the other with them, in order to encourage them. Some people thought that, as a result, when the war was over, the ex-servicemen would be crowding into the churches. Yet it did not happen, and it never has happened that way. The glory of the gospel; is that when the Church is absolutely different from the world, she invariably attracts it. It is then that the world is made to listen to her message, though it may hate it at first. That is how revival comes. That must also be true of us as individuals. It should not be our ambition to be as much like everybody else as we can, though we happen to be Christian, but rather to be as different from everybody who is not a Christian as we can possibly be. Our ambition should be to be like Christ, the more like Him the better, and the more like Him we become, the more we shall be unlike everybody who is not a Christian.

Studies in the Sermon on the Mount, Martyn Lloyd-Jones (emphasis mine)