"Early in the morning it rises, sits upon a twig and sings a song it has learned, while it knows not where to obtain its food, and yet it is not worried as to where to get its breakfast. Later, when it is hungry, it flies away and seeks a grain of corn, where God stored one away for it, of which it never
thought while singing, when it had cause enough to be anxious about its food. Ay, shame on you now, that the little birds are more pious and believing than you; they are happy and sing with joy and know not whether they have anything to eat."
Sermons of Martin Luther, 8 vols., ed. John Nicholas Lenker, Grand Rapids: Baker Book House, 1983, V, p. 114. Matthew 6:24-34.