Here once more we are reminded that our Lord’s method must ever be the pattern and example for all preaching. That is not true preaching which fails to apply its message and its truth; nor true exposition of the Bible that is simply content to open up a passage and then stop. The truth has to be taken into the life, and it has to be lived. Exhortation and application are essential parts of preaching. We see our Lord doing that very thing here. The remainder of the seventh chapter is nothing but a great and grand application of the message of the Sermon on the Mount to the people who first heard it, and to all of us at all times who claim to be Christian.
D. Martyn Lloyd-Jones, Studies in the Sermon on the Mount