In the course of his missionary activity Nanak often visited foreign countries. According to local folklore, he is said to have visited Mecca in the guise of a Muslim devotee. But his not paying heed to Mohammedan etiquette nearly cost him his life. On his first night at Mecca he slept with his feet towards the Kaaba. He was rudely awakened by an Arab clergyman who said, “Who is this sleeping Kaafir (infidel) who lies with his feet towards God?”. To this Guru Nanak replied, “Turn my feet in the direction where God is not”.
Becoming a Nanak fan …
According, to Sikhs all religions are equal. However, there are times, when the Sikhs try prove the another's religion to be inferior. A famous story circulated around Sikhism is how Guru Nanak went to Mecca and pointed his feet at the Kaaba to teach the Muslims, that God is everywhere. The story takes places where a guard tells the Guru to not place his feet toward the direction of the Kaaba, yet the Guru replies by saying God is everywhere. However, what Sikhs fail to realize is that Muslims do not believe that God lives in Mecca. If we have such beliefs then we are not even Muslims. Just like how if a Sikh claims that the Gurus are 10 Gods, then they are not proper Sikhs. – http://www.yanabi.com/index.php?/topic/343610-guru-nanak-in-mecca-part-1/
I looked this up so I could understand more about the story!
to clarify
Muslims DO believe that the Kaaba is a holy piece of God however, and this is why they circle around it when they make pilgrimage there,this is also the reason they always face Mecca when doing thier prayers 5 times a day…kaaba means "house" and this no doubt is where the meaning of this story about Nanak came from. the kaaba is in fact a black stone that was said to have fallen from the heavens on that spot, thus it being the spot where the kaaba ("house" of Allah) was built. It is notable that the black stone used in originally Scotland, the Stone of Scone, which was supposedly stolen by the English king, also has the very same story, is said to be a magical stone of God that fell from the heavens…
Siks in general
While they ARE one of the most even handed religions on earth, and do view with eqanamity all religions, and even while they have a holy city, Amritsar, where all are invited for the meal, regardless of religion, and all sit on the ground, evenly, there are many Sikhs that can be found on various message boards and forums online, that have a less even handed view of all religions, or at least some. I have witnessed many arguments between Sikhs over the subject of Sant Mat, and whether or not it has any relation at all with the Sikh Gurus, as Sant Mat is said to originate from Guru Kabir, who is also held in high regard amongst Sikhs, he and Nanak walked the earth at the very same time, and both performed miraculous things in view of both Muslims and Hindus, and because of this are held in high regard by many from both paths…Guru Arjan, who compiled the Guru Granth Sahib, the Sikh holy book, included some of Kabir's poetry within, as it obviously related and taught the same things as did Nanak's way, however, obviously not all students have achieved Guruhood, and thus, not all of them find it so easy to hold the same regard and pojnt of view that the 10 Gurus did. It is a work in progress for all of us.