As far as I know, the term "non-believers" used by prophet was used to refer to any one who does not realize the all pervading divinity or GOD or ALLAH or PARAMATMA or Heavenly father BY WAY OF SELF-EXPERIENCE OF THE ALL PERVADING DIVINITY. With this meaning, every tom dick and harry who just mugged up the religious book that they were following is also a Non-believer, including 99.99% of muslims as well. This is because, 99.99% of muslims (as well as 99.99% of people of other religions) DOES NOT KNOW WHAT GOD IS BY OWN EXPERIENCE.
The problems that the islamic followers are facing right now is purely because most of the islamic advocates donot have any experience of what ALLAH is. Had they truly known of what is told in Quran by way of own experiences rather than just by reading holy book, some islamic folks would not have been trouble causing to the rest of humanity.
There are saints in Islamic world who truly experienced of the ALL PERVADING DIVINITY INCLUDING IN THEMSELVES AND IN EVERY ONE AS WELL. Those are true islamic ambassadors to the world. This is true with every other religion as well.
