ANSWER: Let us start with a brief definition before we delve into the Bible. Astrology is defined as the study of the heavens (sun, moon, planets, etc.) and their motions under the assumption that they influence events and human activities on earth. Unlike astronomy, which is the scientific study of the universe, astrology is based on a person's interpretation and the meaning they read into what they observe.
The basic idea of astrology, which is trying to predict future events via distant stars and other heavenly bodies, began in ancient Mesopotamia. The Encyclopedia Britannica says this occurred in the third millennium B.C. while the ISBE does not quite agree. They quote a warning based on the stars given to King Ashurbanipal of Assyria (7th century B.C.) which stated, "The planet Venus is approaching the constellation Virgo. The appearance of the planet Mercury is near. Great wrath will come." Such astrology based warnings have, and continue to be, popular in a wide variety of countries and cultures.
Related to astrology are horoscopes, which attempt to predict an individual person's future, based on the time they were born and the movement of the heavens at a particular time period. The word itself is derived from the Greek meaning "one who observes the hour." The Britannica states our current form of horoscopes is really a Greek addition to earlier ideas, such as seeing the sun's path in the sky move through the twelve houses of the zodiac. As an interesting side note, God's word alludes to the zodiac in Job 38:32 (and possibly other places).
The idea that heavenly bodies control our destiny, rather than the Creator of all things, is an ancient delusion. Augustine, the famous Catholic theologian and philosopher who lived when Rome was in decline, and Cicero, the pagan orator of the Roman Republic, made a point of attacking this belief.
Although the Bible does not use the word astrology, it does refer to its practice in several places. For example, the book of Daniel references astrologers serving at the court of King Nebuchadnezzar of Babylon (Daniel 2:27, 4:7). As one would expect, the belief that anything other than the true God steers the destiny of man is rejected in Scripture. In fact, it considers consulting the heavens for guidance as a form of sorcery (Leviticus 19:26 - 28, 31, 20:6). The Eternal warned ancient Babylon about trusting in astrology when he said, "You are exhausted by the multitude of your counsels; now let the astrologers, the stargazers, the monthly prognosticators, stand up, and save you from these things that shall come upon you" (Isaiah 47:13, HBFV).
Ancient Israel was also warned not to indulge those who use the heavens to try to predict the future, "There shall not be found among you [any one] . . . that useth divination, [or] an observer of times, or an enchanter, or a witch . . . " (Deuteronomy 18:10, KJV). A person who is an 'observer of times,' according John Wesley's Explanatory Notes, is someone who superstitiously pronounces some days as lucky and others as unlucky. In the end, astrology does nothing more than pretend to foretell future events based on the absurd idea that celestial bodies, billions of miles away, can have some sort of magical impact on earth.
Pursuing astrology and horoscopes should be avoided completely. If nothing else, basing one's decisions and actions on celestial bodies is a complete and total waste of time! God tells us this is so when he warns us, "Do not learn the way of the heathen (those who do not know the Eternal), and do not be terrified at the signs of the heavens; for the nations are terrified at them. For the customs of the people are VAIN (worthless, useless, accomplishes nothing) . . ." (Jeremiah 10:2 - 3).