Scripture clearly condemns astrology as a practice that is detestable to the Lord in Deuteronomy 18:9-21. Isaiah goes so far as to say that the council of the astrologers and stargazers who make predictions month by month not only wore out the Babylonians but did not save them from their future ruin (Isa. 47:12-15).
Despite the clear condemnation of Scripture, there are still those who maintain that there is a biblical precedent to use stars to chart the future. What they do is they mistakenly cite passages, for example the Magi (Matt. 2), but if you look at the context, it reveals that the star that the magi followed was not used to foretell the future but to forthtell the future. In other words, the star of Bethlehem did not prophesy the birth of Christ, it pronounced the birth of Christ.
One other point is that astrology has been debunked as a pseudo-scientific paradigm that based on the odd predilection that galaxies rather than genes determine inherited human characteristics. Not only so, astrology cannot account for the problem posed by mass tragedies and twins. For example, people with a wide variety of horoscopes all perished on 9/11 and twins born under the same sign of the Zodiac frequently end up with widely diverse futures.
Remember Daniel 2. Even King Nebuchadnezzar’s astrologers recognized the impotence of their craft. When Nebuchadnezzar asked them to remind him of his dream then interpret it? Well, they responded in terror saying no man on earth can do what the king asks. In other words, when Nebuchadnezzar—recognizing they were gaming him—put their lives on the carpet, they exclaimed the truth. They do not know the future nor could they tell the future. They could not as so much be able to tell the dream much less what it portended for the future.
I think what you have with astrology is the subverting of the natural use of the stars, which is of course ordained by God, for a superstitious use of the stars, which God clearly distains. Genesis 1:14-19 points to the natural use of the stars to separate the day from the night, to serve as signs, to mark seasons, days and years, to illuminate the earth. Of course, they can also rightly be used for all kinds of purposes ranging from navigation to natural revelation (Psa. 19:1-6). Therefore, sailors could use astronavigation to chart their course but we as Christians should not use astrology to chart our careers. This is something clearly spoken out against in the very first text that I cited from Deuteronomy 18.
Let no one be found among you who sacrifices his son or daughter in the fire, who practices divination or sorcery, interprets omens, engages in witchcraft, or casts spells, or who is a medium or spiritist or who consults the dead. Anyone who does these things is detestable to the Lord, and because of these detestable practices the Lord your God will drive out those nations before you (Deut. 18:10-12, NIV).
For further reading, please access the following equip.org resources:
Matthew and the Magi: A Case for Astrology? (Gregory Rogers)
What is the Occult? (Hank Hanegraaff)
Witnessing to People in the Occult (Marcia Montenegro)
This blog adapted from the November 13, 2012 Bible Answer Man broadcast.