“The word of God was addressed to John, son of Zechariah, in the desert, and he went through all the Jordan valley. Where else could he go but through the Jordan valley.” Where there would be water at hand to baptize those wishing to amend their lives?

Now the word Jordan means descent or coming down. Coming down and rushing in full flood is the river of God, the Lord our Savior, in whom we were baptized. This is the real, life-giving water, and the sins of those baptized in it are forgiven.

So come, catechumens, and amend your lives so that you may have your sins forgiven in baptism. In baptism the sins of those who cease to sin are forgiven, but if anyone comes to be baptized while continuing to sin, that person's sins are not forgiven.

This is why I urge you not to present yourselves for baptism without thinking very carefully, but to give some evidence that you really mean to change your way of living.

Spend some time living a good life. Cleanse yourselves from all impurity and avoid every sin. Then, when you yourselves have begun to despise your sins, they will be forgiven you. You will be forgiven your sins if you renounce them.

The teaching of the Old Testament is the same. We read in the prophet Isaiah: “A voice cries out in the desert: Prepare a way for the Lord. Build him a straight highway.”

What way shall we prepare for the Lord?

A way by land? Could the Word of God travel such a road? Is it not rather a way within ourselves that we have to prepare for the Lord?

Is it not a straight and level highway in our hearts that we are to make ready? Surely this is the way by which the Word of God enters, a way that exists in the spaciousness of the human body.

The human heart is vast, broad, and capacious, if only it is pure. Would you like to know its length and breadth? See then what a vast amount of divine knowledge it can contain.

Solomon says:

He gave me knowledge of all that exists; he taught me about the structure of the universe and the properties of the elements, the beginning and the end of epochs and the periods between, the variations in the seasons and the succession of the months, the revolution of the year and the position of the stars, the nature of living things and the instincts of wild animals, the force of the winds and the thoughts of human beings, the various kinds of plants and the medicinal properties of roots. (Wisdom 7:17)

You must realize that the human heart is not small when it can contain all this. You ought to judge it not by its physical size but by its power to embrace such a vast amount of knowledge of the truth.

But so that I may convince you that the human heart is large by a simple example from daily life, let us consider this. Whatever city we may have passed through, we have in our minds. We remember its streets, walls, and buildings, what they were like and where they were situated. We have a mental picture of the roads we have traveled. In moments of quiet reflection our minds embrace the sea that we have crossed. So, as I said, the heart that can contain all this is not small!

Therefore, if what contains so much is not small, let a way be prepared in it for the Lord, a straight highway along which the Word and Wisdom of God may advance. Prepare a way for the Lord by living a good life and guard that way by good works. Let the Word of God move in you unhindered and give you a knowledge of his coming and of his mysteries. To him be glory and power for ever and ever. Amen.

On Luke's Gospel 21: PG 13, 1855-1856