But the Gospel is not only news. It is first news, and then it is doctrine. Doctrine means teaching, explaining, clarifying. Doctrine is part of the gospel because news can’t be just declared by the mouth of a herald – it has to be understood in the mind of the hearer. If the town crier says, “Amnesty is herewith published by the mercy of your Sovereign,” someone will ask, “what does ‘amnesty’ mean?” There will be many questions when the news is announced, “What is the price that has been paid?” “How have we dishonored the King?” When the gospel is proclaimed, it must be explained. …Unintelligible news is not even new, let alone good.

Gospel doctrine matters because the good news is so full and rich and wonderful that it must be opened like a treasure chest, and all its treasures brought out for the enjoyment of the world. Doctrine is the description of these treasures. Doctrine describes their true value and why they are so valuable. Doctrine guards the diamonds of the Gospel from being discarded as mere crystals. Doctrine protects the treasures of the Gospel from the pirates who don’t like the diamonds but who make their living trading them for other stones. Doctrine polishes the old gems buried at the bottom of the chest. It puts the jewels of the Gospel truth in order on the scarlet tapestry of history so each is see in its most beautiful place.

And all the while, doctrine does this with its head bowed in wonder that it should be allowed to touch the things of God. It whispers praise and thanks as it deals with the diamonds of the King. … and on its knees Gospel doctrine knows it serves the herald. The Gospel is not mainly about being explained. Explanation is necessary, but it is not primary. A love letter must be intelligible, but the grammar and logic are not the point.

The Gospel is good news. Doctrine serves that.

- John Piper, God is the Gospel

Seen at Both Saint and Sinner.