It is all over everywhere: newspapers,magazines,internet etc.They all point to know the future.But should a good xtian or muslim believe in horoscope/astrology,

Lets see,

What do you mean by good christians or good muslim.As for me a good christian/muslim is one that keeps an open mind, pushing aside his religious dogmas so as to get a clearer understanding of his or her holy book.With this statement, i believe you know where i am heading to.

believe only in what the bible says

Leaving the Bible aside, why would I want to believe in such? What has the stars got to do with my personal life? I personally don't believe in such except when it's something good

These types of spiritism along with all other forms are tools used by Satan and his demons to mislead us. These mediums and horoscopes and psychics can give us information that may seem to help us but can we trust guidance from Satan the devil who the bible tells us is a liar?

It also harms us because it can destroy our relationship with God (Deuteronomy 18:10,12-anyone who employs divination,practicer of magic, who looks for omens, a sorcerer, or one who binds others with spells, consults a spirit medium, or a professional forteller of events, or anyone who inquires or the dead. Anyone doing these things is detestable to God). Also at Leviticus 19:31 it says "Do not turn yourselves to the spirit mediums and do not consult professional foretellers of events so as to become unclean by them. I am Jehovah your God."

Its really clear on the answer. I thank God for the bible, it always amazes me.