As usual, Guru Nanak woke up early in the morning, before sunrise and walked with Mardana to the nearby river named “Vaee” (vyeI) to take a bath. Guru Nanak stepped into the river and disappeared. Mardana tried to find Guru Nanak, but he could not see him anywhere, so he went back to the village and told everyone what happened.   Guru Nanak’s family and other people from the village ran to the river and searched for the Guru, but nobody could find him. Finally, they all gave up. They thought that maybe he had drowned in the water, so they all left.   Everyone was saddened by what had happened. Jai Ram was about to write a letter to Guru Nanak’s parents telling them that their son drowned in the river, but Bibi Nanaki stopped him. She said that Guru Nanak is still alive. She was the only one who kept faith in the Guru. She said that there is no way Guru Nanak is dead, because he still has to save a lot of people in this world. She showed us all that we should never lose faith in our Guru.   Three days passed by and there was still no sign of Guru Nanak. The Guru was gone to such a place where there is no time. Over these three days, Guru Nanak went into deep meditation and came to the realization that it is time to go out and spread the message of God and show people the path of truth. 

      On the third day, Guru Nanak came out of the river and Mardana was the first to see him. Today there is a temple built where Guru Nanak was first spotted after he came out of the river. This temple is called Gurdwara Sunt Ghatt Saheb (gurduAwrw sMq Gwt swihb). 

      At this moment, Guru Nanak spoke the famous Mool Mantar. 
He then came back to the village of Sultanpur, but did not speak to anyone. Many people, including Daulat Khan, Mardana, and Jai Ram tried to talk to him, but the Guru did not speak to any of them. 
Finally Guru Nanak broke his silence by saying the following words:   

jo nw koeI ihMdU hY nw muslmwn hY 
                                            (Pratan Junam Sakhi) 

Translation: 

“There is no Hindu, there is no Muslim”.   

People heard what Guru Nanak was saying and they thought that maybe he had gone crazy or maybe he was possessed by a ghost. A mullah (Muslim priest) was called to check and see if Guru Nanak was okay. The mullah wrote many mantras on a piece of paper and put them around the Guru who was sitting with his eyes closed. He started to read his mantras and blowing smoke at the Guru. Guru Nanak opened his eyes and looked at the mullah. 
  The mullah said, “There is a ghost inside of him.”   The mullah asked Guru Nanak, “Tell me ghost, what is your name?”   Guru Nanak answered with the following hymn: 

                                                  mwrU mhlw 1 ] 
koeI AwKY BUqnw ko khY byqwlw ] koeI AwKY AwdmI nwnku vycwrw ]1] BieAw idvwnw swh kw nwnku baurwnw ] hau hir ibnu Avru n jwnw ]1] rhwau ]qau dyvwnw jwxIAY jw BY dyvwnw hoie ] eykI swihb bwhrw dUjw Avru n jwxY koie ]2]qau dyvwnw jwxIAY jw eykw kwr kmwie ] hukmu pCwxY Ksm kw dUjI Avr isAwxp kwie ]3]
qau dyvwnw jwxIAY jw swihb Dry ipAwru ] mMdw jwxY Awp kau Avru Blw sMswru ]4] 

Translation: 
  Some call him a ghost; some say that he is a demon. Some call him a mere mortal; O, poor Nanak! Crazy Nanak has gone insane, after his Lord, the King. Know of none other than the Lord. He alone is known to be insane, when he goes insane with the Fear of God. He recognizes none other than the One Lord and Master. He alone is known to be insane, if he works for the One Lord. Recognizing the Hukam, the Command of his Lord and Master, what other cleverness is there? He alone is known to be insane, when he falls in love with his Lord and Master. He sees himself as bad, and all the rest of the world as good. 

     After hearing these words from the Guru, everyone realized that Guru Nanak was not crazy. However, they were still curious as to why the Guru had said that there is no Hindu or Muslim. 
  

     Nawab Daulat Khan asked Guru Nanak why he said that there is no Hindu or Muslim. Daulat Khan said, “I follow the Muslim religion, am I not a Muslim?”   Guru Nanak responded that these religions are started by man, there is only one God for all of mankind. Every religion has a different name for God, such as Allah and Ram, but these are names for the same God. 
      Guru Nanak then said the following hymn: 
  
                                         sloku mÚ 1 ] 
muslmwxu khwvxu musklu jw hoie qw muslmwxu khwvY ] 
Avil Aauil dInu kir imTw mskl mwnw mwlu muswvY ] 
hoie musilmu dIn muhwxY mrx jIvx kw Brmu cukwvY ] 
rb kI rjwie mMny isr aupir krqw mMny Awpu gvwvY ] 
qau nwnk srb jIAw imhrMmiq hoie q muslmwxu khwvY ]1]   

Translation:   

It is difficult to be called a Muslim; if one is truly a Muslim, then he may be called one. First, let him savor the religion of the Prophet as sweet; then, let his pride of his possessions be scraped away. Becoming a true Muslim, a disciple of the faith of Mohammed, let him put aside the delusion of death and life. As he submits to God's Will, and surrenders to the Creator, he is rid of selfishness and conceit. And when, O Nanak, he is merciful to all beings, only then s hall he be called a Muslim. 

       So the Guru has told us that you cannot become Muslim just by calling yourself one, but you have to follow what the Muslim religion teaches. This is also true for the Hindu religion. The same is true for the Sikh religion - you cannot become a Sikh by calling yourself one; you can only truly call yourself a Sikh when you follow the teachings of the Guru.