Astrology is a pseudo-science concerned with the influences of the stars upon human affairs and predicting future events by the aspects and positions of the stars.
Astronomy is a real science concerned with the magnitudes, motions, constitution, etc., of heavenly bodies.
In the field of astronomy, the Babylonians were the masters of the ancient world and their astronomers put this science to the service of astrology. This science, which continually developed from the period of Hammurabi (1728-1686 B.C.), received new vitality with the Chaldean invasion of Babylonia. Because of strict astronomical observations (e.g., lunar and solar eclipses), every single year from 893 B.C. to A.D. 160 can be definitely accounted for according to Assyrian, Babylonian, and Greek chronology. Two Chaldeans, namely, Baburianus (c. 508 B.C.) and Cidenas (c. 379 B.C.) made the greatest advances in Babylonian astronomy, the latter of whom discovered the precession of the equinoxes nearly 250 years before it was scientifically explained by the Greek Hipparechus (c. 130 B.C.).
The astronomical data were also used to forecast the future destinies of man. Thus astrology arose in Babylonia as the mischievous handmaid of astronomy; it later became popular among the Greeks and Egyptians. It was alleged that everything was written beforehand in the heavens and that everything happened according to the positions and aspects of the heavenly bodies. It was maintained that an astrologer could, by knowing the position of the planets and stars when a person was born, foretell his destiny. Calculations of periods of time and of the destinies of peoples, the role of the planets and stars, the unceasing action of evil spirits or demons, the consultation of omens, preservative actions against harmful agents by using talisman, amulets, charms, etc., appeared everywhere in the religious domain under the guise of science.
The astrologers divided up the heavens into zones, according to the signs of the zodiac, and from the movement of these zones of the sun, moon and planets foretold the fate of nations and individuals. The observed the courses of the stars and from them, forecast future events. They made monthly calendars of lucky and unlucky days.
Actually, there is no such thing as luck in the world, neither are there lucky or unlucky days or numbers. All things are arranged or permitted by Divine Providence.
In the Old Testament, the Prophet Isaiah (754-694) ironically invites the Babylonians to make use of her customary charms (enchanters) and spells, to protect themselves from the wrath of God. Isaiah prophesies that the astrologers will burn like stubble in the destructive fire of judgment:
“Stand fast in your enchantments and your many sorceries, with which you have labored from your youth; perhaps you may be able to succeed, perhaps you may inspire terror. You are wearied with your many counsels; let them stand forth and save you, those who divide the heavens, who gaze at the stars, who at the new moons predict what* shall befall you. Behold, they are like stubble, the fire consumes them; they cannot deliver themselves from the power of the flame. No coal for warming oneself is this, no fire to sit before! Such to you are those with whom you have labored, who have trafficked with you from your youth; they wander about each in his own direction; there is no one to save you” (Is 47:12-15).
Divination
Divination seeks guidance from a higher power apart from God. Divination is any attempt to foresee future contingencies which human beings can know neither naturally nor by divine revelation. In taking seriously omens, Astrology, automatic writing, or reading palms, cards, tealeaves, and so forth, people engage in divination. Implicit in these practices is recourse to something more than human, which is assumed either to know the future, to determine it, or both. Such a higher power other than God would be either personal and demonic or some sort of impersonal, cosmic, ruling force, which subjected human life to inexorable fate. In either case, something other than God is regarded as if it were divine, insofar as enlightenment is sought from it to supplement the guidance God has made available.
The stars exercise no influence whatever upon human life and human affairs, and the casting of a horoscope or diagram of the heavens at the birth of a child in order to foretell its future is downright foolishness. St. Augustine attacked it strongly in his City of God:
“But that all things come to pass by fate, we do not say; nay we affirm that nothing comes to pass by fate; for we demonstrate that the name of fate, as it is wont to be used by those who speak of fate, meaning thereby the position of the stars at the time of each one’s conception or birth, is an unmeaning word, for astrology itself is a delusion’ (Book V (1), Chap. 9).
St. Thomas Aquinas also robustly condemned astrology:
“If anyone applies the observations of the stars in order to foreknow casual or fortuitous events, or to know with certitude future human actions, his conduct is based on a false and vain opinion; and so the operation of the demon introduces himself therein, wherefore it will be a superstitious and unlawful divination” (Summa, IIa. IIae., Q. 95, art 5).
Astrology was condemned by the Creed of the Council of Toledo of the year 400 [and 447]:
“If anyone holds that astrology and the interpretation of stars (sic) ought to be believed, let him be anathema” (35 [15.]).
Fatalism Denies Free Will and Reason
The Catholic Church condemns astrology as a pagan superstition, which by encouraging fatalism leads to the denial of Divine Providence.
St. Basil the Great (329? – 1 January, 379 states,
“Now the Greeks declare that all our affairs are controlled by the rising and setting and collision of these stars, viz., the sun and moon: for it is with these matters that astrology has to do. But we hold that we get from them signs of rain and drought, cold and heat, moisture and dryness, and of the various winds, and so forth, but no sign whatever as to our actions. For we have been created with free wills by our Creator and are masters over our own actions. Indeed, if all our actions depend on the courses of the stars, all we do is done of necessity: and necessity precludes either virtue or vice. But if we possess neither virtue nor vice, we do not deserve praise or punishment, and God, too, will turn out to be unjust, since He gives good things to some and afflicts others. Nay, He will no longer continue to guide or provide for His own creatures, if all things are carried and swept along in the grip of necessity. And the faculty of reason will be superfluous to us: for if we are not masters of any of our actions, deliberation is quite superfluous. Reason, indeed, is granted to us solely that we might take counsel, and hence all reason implies freedom of will.
“And, therefore, we hold that the stars are not the causes of the things that occur, nor of the origin of things that come to pass, nor of the destruction of those things that perish. They are rather signs of showers and changes of air. But, perhaps, someone may say that though they are not the causes of wars, yet they are signs of them. And, in truth, the quality of the air, which is produced by sun, and moon, and stars, produces in various ways different temperaments, and habits, and dispositions. But the habits are amongst the things that we have in our own hands, for it is reason that rules, and directs, and changes them” (The Great and Exact Exposition of the Orthodox Faith, Bk II, Chap. VII).
The Catechism of the Catholic Church
The Catechism of the Catholic Church states: “All forms of divination are to be rejected: recourse to Satan or demons, conjuring up the dead or other practices falsely supposed to “unveil” the future. Consulting horoscopes, astrology, palm reading, interpretation of omens and lots, the phenomena of clairvoyance, and recourse to mediums all conceal a desire for power over time, history, and, in the last analysis, other human beings, as well as a wish to conciliate hidden powers. They contradict the honor, respect, and loving fear that we owe to God alone” (2116).
References:
John E Steinmueller, and Kathryn Sullivan, Catholic Biblical Encyclopedia, Joseph F. Wagner, Inc., 1956, p. 125.
Germain Grisez, Christian Moral Principles, The Way of the Lord Jesus Vol. II, http://www.wayofthelordjesus.org/lcl.cfm?page=go_next&np=doc_61