But see how beautifully [king David] can speak! “I am,” he says, “the Lord’s sheep; He feeds me in a green pasture.” For a natural sheep nothing can be better than when its shepherd feeds it in pleasant green pastures and near fresh water. Where that happens to it, it feels that no one on earth is richer and more blessed than it is. For it finds there whatever it might desire: fine, lush, heavy grass, from which it will grow strong and fat; fresh water, with which it can refresh and restore itself whenever it likes; and it has its joy and pleasure there, too. At this point David would also say that God had shown him no greater grace and blessing on earth than this, that he was permitted to be at a place and among people where God’s Word and dwelling place and the right worship were to be found. Where these treasures are found, there things prosper well, both in the spiritual and in the secular realm. It is as if he were saying: “All people and kingdoms on earth are nothing. They may be richer, more powerful, and more splendid than we Jews, and they may also boast mightily of what they have. Moreover, they may glory in their wisdom and holiness, for they, too, have gods whom they serve. But with all their glory and splendour they are a mere desert and wilderness. For they have neither shepherd nor pasture, and therefore the sheep must go astray, famish, and perish. But though we are surrounded by many deserts, we can sit and rest here, safe and happy in Paradise and in a pleasant green pasture, where there is an abundance of grass and of fresh water and where we have our Shepherd near us, who feeds us, leads us to the watering place, and protects us. Therefore we cannot want.”
Martin Luther, Luther’s Works, Vol. 12: Selected Psalms I, ed. Jaroslav Jan Pelikan, Hilton C. Oswald, and Helmut T. Lehmann (Saint Louis: Concordia Publishing House, 1999), 160–161.