Those who meddle with astrologers and sorcerers (and like practices) put themselves on a collision course with God's judgment.
The truth is more valuable than any earthly possession and it would be worth a man selling everything he owns just to possess the truth.
God is "a God of truth" and the words that proceed forth from Him reflect His nature. As such, the words of God are just as true as the God of the words.
There are many things in this life that are not sinful in and of themselves, but when they are misused they can be deemed as sinful or harmful.
