Who is ‘Waheguru’ or God in Sikhism?

गुरु ग्रन्थ साहेब, राग आसावरी, महला 1 के कुछ अंश -

साहिब मेरा एको है। एको है भाई एको है।
आपे रूप करे बहु भांती नानक बपुड़ा एव कह।। (पृ. 350)
जो तिन कीआ सो सचु थीआ, अमृत नाम सतगुरु दीआ।। (पृ. 352)​
गुरु पुरे ते गति मति पाई। (पृ. 353)​
बूडत जगु देखिआ तउ डरि भागे।​
सतिगुरु राखे से बड़ भागे, नानक गुरु की चरणों लागे।। (पृ. 414)
मैं गुरु पूछिआ अपणा साचा बिचारी राम। (पृ. 439)

Guru Nanak dev, the founder of Sikhism had given us many clues in Guru Granth Saheb that we can attain salvation only from Real Supreme Guru / Tattavdarshi Guru. Supreme Guru plays important role in human life. The real name of God in different native languages is KavirDev (in Sanskrit language in the Vedas), Hakka Kabir (in regional language in Guru Granth Sahib on page no. 721).

He said that:-

"हका कबीर करीम तू, बेऐब परवरदिगार"

"Waheguru", (Wondrous Destroyer of darkness) is the distinctive representation of God's name in the Sikh tradition. It means "Wonderful Teacher" in the Punjabi language.

Information about the Guru of Nanak Dev Ji

In the below-mentioned sacred speech, Shri Nanak Ji is himself accepting that Sahib (Supreme God) is only One, and my Guru ji gave updesh Naam mantra to me; He only acquires different forms i.e. He only is SatPurush; He only assumes Jinda form.

He only sitting in the form of a weaver (Dhaanak) also plays the role of an ordinary person i.e. devotee. Seeing the whole world burning in the fire of birth-death and the results of their actions because of doing pooja opposite to the scriptures, running with the fear of the life being wasted, I took refuge in Guru Ji’s feet.

In Guru Granth Sahib, Raag ‘Siri’ Mehla 1, on Page no. 24, Shabd no. 29

Shabd/Hymn —

Ek suaan dui suaani naal, bhalke bhaunkahi sada biaal
Kud chhura mutha murdaar, dhaanak roop raha kartaar |1|

Mae pati ki pandi na karni ki kaar çuh bigad roop raha bikraal
Tera ek naam taare sansaar, main eho aas eho aadhaar ||

Mukh ninda aakha din raat, par ghar johi neech manaati ||
Kaam krodh tan vasah chandaal, dhaanak roop raha kartaar ||2||

Faahi surat malooki ves, uh thagvaada thaggi des ||
Kharaa siaana bahuta bhaar, dhaanak roop raha kartaar ||3||

Main keeta na jaata haraamkhor, uh kia muh desa dusht chor ||
Nanak neech kah bichaar, dhaanak roop raha kartaar ||4||

Kabir Parmeshwar recited the Shrishti Rachna (Creation of Universe) and said that I am a complete God, my place is in Sachkhand. You are my soul. Kaal (Brahm) distracts all souls with confusing knowledge and is troubling many kinds of beings in their bodies.

■ Supreme God Kabir

Supreme God Kabir Guru of Nanak Dev ji again said, I will give you Satnaam (recitation of Satyanam / actual mantra) which Kaal (Brahm) has kept secret and is not in any scripture.

 Ehu jeeu bahute janam bharmiaa, ta Satiguru shabad sunaaiya || (Pg 465)

ए ठगवारा ठग्गी  देश,  खरा सयाना भोते भार धानक रूप रहा करतार। 

■ Baba Nanak

emphasizes here on ‘Genuine name’ given by Complete Guru who has bestowed the true mantra on to him (Nanakji) and is saying that this soul (Jeevaatma) kept wandering in the cycle of birth and death for a long time. 

Nanak Devji’s Satlok Visit

Shri Nanak Ji requested Kabir Sahib to seek Sachkhand and ultimate One God (Akaal Purush). Then, Kabir Sahib took Shri Nanak Ji's soul to Satyaloka. At Satlok, Shri Nanak Ji saw that Supreme God Kabir Sahib (KavirDev) is sitting in His actual form.

“Hakka Kabir kareem tu, beaeb Parvardigaar
Nanak bugoyad jan tura, tere chaakraan paakhaak”

There is so much brightness in Sachkhand, Shri Nanak saw that an infinitely bright illumined human-like God (who was sitting on the throne) as if in one hair follicle, there is more brightness than the combined light of crore suns and crore moons (but there is no warmth). On his own another form (Jinda Mahatma जिन्दा महात्मा), Kabir Sahib started moving whisk / doing chanvar (चंवर) as a humble servant.

Then Shri Nanak Ji thought that this is the Ultimate God who is sitting on the throne; Kabir will be a servant here, but the lok is different from all. God is very effulgent. While Nanakji is thinking all this, the effulgent form of God stood up and KavirDev sat down on the throne. Then, the actual visible effulgent form of God started moving whisk on Kabir Sahib. Thereafter, Kabir Sahib’s effulgent form vanished into Kabir Sahib.

And only, Supreme God KavirDev is sitting on the throne; and the chavar /Whisk began to drift on its own. Then Nanak Ji said that You are the Master and I recognize you as Waheguru from Satyanaam. This process took three days. Sahib Kabir Ji returned the soul of Nanak to the body. On the third day, Shri Nanak came to his senses. After realizing Kabir Saheb as a God in Satlok, Shri Nanak Ji said ‘ Waheguru’ Satnaam.

“Jhanki dekh kabir ki nanak kiti Wah, WaH sikha k gal padi ab kaun chutave tha.”

Waheguru is a term most often used in Sikhism to refer to God, the Supreme Being or the creator of all. 

Kabir Saheb had said :-

गुरु गोविंद दोनों  खड़े, काके लागू पाए, बलिहारी गुरु आपने जिन गोविंद दियो मिलाए