"But of the fruit of the tree which is in the midst of the garden, God hath said, Ye shall not eat of it, neither shall ye touch it, lest ye die."
He didn't just say we can't eat of it, He said we can't touch it! We must stay as far away from sin as we possibly can! The more we play around in the world the more tempted we will become and before we know it we will have given our selves to the devil.
2 Corinthians 7:1
"Having therefore these promises, dearly beloved, let us cleanse ourselves from all filthiness of the flesh and spirit, perfecting holiness in the fear of God."
"If any man among you seem to be righteous, and bridleth not his tongue, but deceiveth his own heart, this man's religion is vain. Pure religion and undefiled before God and the Father is this, to visit the fatherless and widows in their affliction, and to keep himself unspotted from the world."
"Ye adulterers and adulteresses, know ye not that the friendship of the world is enmity with God? whosoever therefore will be a friend of the world is the enemy of God."
"Submit yourselves therefore to God. Resist the devil, and he will flee from you. Draw nigh to God and he will draw nigh to you. Cleanse your hands, ye sinners; and purify your hearts, ye double minded."
1 John 2:15
"Love not the world, neither the things that are in the world. If any man love the world, the love of the Father is not in him."
I'm just going to let the Word of God speak. I think these verses alone say enough. They pretty much sum it all up. There is nothing I can add to this, if these scriptures don't get the point across I don't know what will.