Martyn Lloyd-Jones
We must stand firm in the truth, in the message, for without it we have no power. We may be very nice and kind to one another, but that will not convince the world of sin, and bring them to Jesus. The truth alone can do that.

The Law and the Gospel are two keys. The Law is the key that shutteth up all men under condemnation, and the Gospel is the key which opens the door and lets them out.
William Tyndale