by Shaykhul Islam Mumammad ibn Abdul Wahhaab Explained By Shaykh Saalih Al-Fawzaan
Allah the Most High says, "I created not the Jinn and humans except that they should worship me (alone)."
Any type of worship mingles with even a mustard seed amount of shirk, all of the worship unto Allah (All kinds of Ibadah) will be destroyed and invalidated. And whoever committed Shirk would be thrown ito the Hel-Fire eternally. So every muslim should realize all the four principles of Shirk are the most important matter for him to learn.