Sahih Muslim Book 1, Hadith Number 168.

Chapter : He who dies associating none with Allah would enter Paradise and he who dies as a polytheist would enter the fire of Hell.

It is narrated on the authority of Jabir that a man came to the Apostle of Allah (may peace be upon him) and said: Messenger of Allah, what are the two things quite unavoidable? He replied: He who dies without associating anyone with Allah would (necessarily) enter Paradise and he who dies associating anything with Allah would enter the (Fire of) Hell.