Bhagavad Gita 10.42अथवा बहुनैतेन किं ज्ञातेन तवार्जुन।विष्टभ्याहमिदं कृत्स्नमेकांशेन स्थितो जगत् ॥

The Lord concludes Having established or pervaded this whole world with one fragment of Myself, I remain.This verse is based on the declaration in the Purusha Sukta (RigVeda10.90.3) that One quarter of Him is all the cosmos the three quarters are the divine transcendent Reality.I exist supporting this whole world by one part, by one limit, or by one foot. One part of Myself constitutes all beings.All beings form His foot (Taittiriya Aranyaka 3.12). The whole world is one Pada or foot of the Lord. Amsa (part) or Pada (foot) is mere Kalpana or imagination or account of our own ignorance,or limiting adjunct. In reality Brahman is without any such parts or limbs and is formless.Arjuna has now a knowledge of the glories of the Lord. He is fit to behold the magnificent cosmic form of the Lord. Lord Krishna prepares Arjuna for this grand vision by giving him a description of His glories.Arjuna says O Lord, I now realise that the whole world is filled by Thee. I now wish to behold the whole universe in Thee with my eye of intuition.