#गुरुनानकजी_के_गुरु_कौन
After seeing Kabir Saheb in Satlok as the creator of the whole universe, the word "Waheguru" came out of Shri Nanak Ji's mouth. Because Nanak Ji had found Kabir Saheb as a living Mahatma who was his Guru.
Hakka Kabir Karim Tu