Letter 443: With all your strength, best of men, you ought to practice virtue.

Just as a thing fixed upon a wheel accomplishes nothing against the wheel itself -- for it is overcome by the wheel's exceedingly swift rotation -- so also the wandering stars stand in relation to the motion of the fixed stars. Now the argument that refutes those who sometimes deify them as gods and other times compare them to ants, I merely note in passing, since I am pressing on to another matter, and I shall leave it aside for now. But I shall come to the question at hand. So much, then, for their views. For my part, I believe that Scripture uses this name either in its proper sense, or by way of adaptation, or following common usage, because the sun, the moon, and the five other stars -- not known to many -- the shining one, the radiant one, the gleaming one, the fiery one, and indeed the morning star, are classed among the wandering stars by those more foolish than you, who imposed upon them the names of certain mortals who ruled on earth and lived shamefully, though they ended their lives in fame. The sun traverses the northern and southern regions in breadth over the course of a year; the moon does so monthly -- whence, I believe, comes the word "month," not because the moon takes a crescent shape, as some say, but because she completes her entire course each month, for the moon is called "mene." All the other stars similarly complete this circuit in proportion to their own orbits and courses, and for this reason they are called "wanderers." Nevertheless, whether this or that explanation is true, it proclaims the knowledge of the Creator who both established their order and laid down their law, as he himself says: "I gave commandment to the stars." And the Psalmist, showing that on earth the divine commandment was transgressed -- humans having deserted of their own will into lawlessness -- while in heaven it was kept, said: "Forever, O Lord, your word endures in heaven." But if, because of the saying "I gave commandment to the stars," certain persons would define them as rational beings with free will -- for I know some, not only outside the faith but even among believers, who have held this doctrine -- I consider this inquiry superfluous and profitless.