Against Astrology

Sed quolibet modo superstitionis haec ab hominibus nuncupentur, sunt tamen sidera quae Deus in mundi principio condidit, ac certo motu distinguere tempora ordinavit. Horum igitur signorum observationes, vel geneses, vel cetera superstitiosa, quae se ad cognitionem siderum coniungunt, id est ad notitiam fatorum, et fidei nostrae sine dubitatione contraria sunt, sic ignorari debent a Christianis, ut nec scripta esse videantur. Sed nonnulli siderum pulcritudine et claritate perlecti in lapsus stellarum caecatis mentibus conruerunt, ita ut per subputationes noxias, quae mathesis dicitur, eventus rerum praescire posse conentur: quos non solum Christianae religionis doctores, sed etiam gentilium Plato, Aristoteles, atque alii rerum veritate conmoti concordi sententia damnaverunt, dicentes confusionem rerum potius de tali persuasione generari. Nam sicut genus humanum ad varios actus nascendi necessitate premerentur, cur aut laudem mereantur boni aut mali legum percipiant ultionem? Et quamvis ipsi non fuerint caelesti sapientiae dediti, veritatis tamen testimonio errores eorum merito perculerunt. Sanctus Isidorus Hispalensis, Etymologiae, Liber III, Caput LXXI Source: Migne PL 82.182c-184a

But by whatever type of superstition the stars were named by men, they were established by God in the beginning of the world, and He ordained that their particular motion distinguish the seasons. Therefore observation of the constellations, or horoscopes, or other superstitions that are attached to the study of the stars, that is, for the knowledge of fate, are without doubt contrary to our faith and should be ignored by Christians, indeed as if it were that they had never been written about. Yet some lured by the beauty and brightness of the constellations, with minds so blinded, have raced into error about the stars, so that through noxious computations, which is called astrology, they try to foresee events. And not only those learned in the Christian religion but even the pagan Plato and Aristotle and others, in harmony of thought, were moved by the truth of things to condemn this, saying that such an idea caused a confusion of things. For if the human species is compelled to various acts by the necessities of birth, then why should the good merit praise and why should the wicked receive the punishment of the laws? Thus though those pagan wise men were not devoted to heavenly matters, they rightly threw down these errors by their testimony of truth. Saint Isidore of Seville, The Etymologies, Book 3, Chapter 71