It is virtually impossible to have two masters. Our heart can only be truly devoted to one while we'll hate the other. Matthew 6:24 tells us this better. If there is one attribute about God it is that He is a jealous God. He does not tolerate our service to anyone else or deity except to Him alone. Any form of worship that is not directed to God alone displeases Him.
Idol worshipping contradicts everything we stand for and believe in Christianity. Coming to God means surrendering and forsaking all. Things like idols can keep us detached from the presence of God.
Exodus 20:3 KJV
Thou shalt have no other gods before me.
Exodus 20:4
Thou shalt not make unto thee any graven image, or any likeness of any thing that is in heaven above, or that is in the earth beneath, or that is in the water under the earth:
This is the commandment of God. This is part of what it takes to walk with God. It is either we choose Him are something else. But trying to mix Him up with other gods can never work out.
Habakkuk 2:19
Woe unto him that saith to the wood, Awake; to the dumb stone, Arise, it shall teach! Behold, it is laid over with gold and silver, and there is no breath at all in the midst of it.
Someone who participates in idol worshipping does not fully know his potential he possesses as being created in the image of God. God gave us dominion that we may have power over everything on earth and be gods to them and not things being gods to us. Idol worshipping should never be the way of the christian.