God expects His people to avoid unholy practices (i.e., divination, observing of times, witchcraft, wizardry, necromancing) that ensnare the world.
There are two categories of sin: sins against God and sins against man. By default, every sin is against God. Yet, not all sin is against man.
Most people view sin as a private or earthy matter. Yet, every sin is against the Lord. In truth, men can sin against the Father, the Son, and the Spirit.