You see, He is making the birds our schoolmasters and teachers. It is a great and abiding disgrace to us that in the Gospel a helpless sparrow should become a theologian and a preacher to the wisest of men, and daily should emphasize this to our eyes and ears, as if he were saying to us: “Look, you miserable man! You have house and home, money and property. Every year you have a field full of grain and other plants of all sorts, more than you ever need. Yet you cannot find peace, and you are always worried about starving. If you do not know that you have supplies and cannot see them before your very eyes, you cannot trust God to give you food for one day. Though we are innumerable, none of us spends his living days worrying. Still God feeds us every day.” In other words, we have as many teachers and preachers as there are little birds in the air. Their living example is an embarrassment to us. Whenever we hear a bird singing toward heaven and proclaiming God’s praises and our disgrace, we should feel ashamed and not even dare to lift up our eyes. But we are as hard as stone, and we pay no attention even though we hear the great multitude preaching and singing every day. Look at what else the dear little birds do. Their life is completely unconcerned, and they wait for their food solely from the hands of God. Sometimes people cage them up to hear them sing. Then they get food in abundance, and they ought to think: “Now I have plenty. I do not have to be concerned about where my food is coming from. Now I have a rich master, and my barns are full.” But they do not do this. When they are free in the air, they are happier and fatter. Their singing of Lauds and of Matins to their Lord early in the morning before they eat is more excellent and more pleasant. Yet none of them knows of a single grain laid away in store. They sing a lovely, long Benedicite and leave their cares to our Lord God, even when they have young that have to be fed. Whenever you listen to a nightingale, therefore, you are listening to an excellent preacher. He exhorts you with this Gospel, not with mere simple words but with a living deed and an example. He sings all night and practically screams his lungs out. He is happier in the woods than cooped up in a cage, where he has to be taken care of constantly and where he rarely gets along very well or even stays alive. It is as if he were saying: “I prefer to be in the Lord’s. kitchen. He has made heaven and earth, and He Himself is the cook and the host. Every day He feeds and nourishes innumerable little birds out of His hand. For He does not have merely a bag full of grain, but heaven and earth.”
Martin Luther, vol. 21, Luther’s Works, Vol. 21 : The Sermon on the Mount and the Magnificat.