COSMIC EGG (HIRANYAGARBHA) The True Lord created the world with his own hands. He broke the Cosmic Egg into two parts. He united the ends of both the parts, and separated them from each other from the middle. (The middle portion became the space). In this way he made the earth and the sky as places for living. He created day and night and also fear and love.

He Who has created, Perceives His creation, there is no other Creator. (Bilawal M. l, Thitli, p. 839) The above reference is a pointer to the Cosmic Egg or Hiranyagarbha, which is a name for Brahma, because he is said to have been born from the Golden Egg.Guru Nanak Dev has rejected the myth given in the 121st hymn of the tenth book of Rig Veda, wherein it is stated that Brahma, the Lord of all beings upholds heaven and earth, and gives life and breath. According to this hymn, Brahma is the god of all gods and all the gods obey his commands. Guru Nanak Dev does not consider this Great god as Brahma, but only the Transcendental and Immanent Brahman.

References :

1. Kohli, Surindar Singh (ed), Dictionary of Mythological References in Guru Granth Sahib, 1993