Meaning
O, Arjuna! I have revealed My Primal, Infinite, and supremely radiant Cosmic Form to you, through my Creative Power, out of my pleasure. This form has never been seen by anyone else before. (11:47)
Commentary
In His previous incarnation as Bhagawān Rāma, the Lord had shown His Cosmic Figure to mother Kaushalyā and as baby Krishna to His mother, Yashodā. But the Cosmic Form revealed to Arjuna was significantly different from all those. This difference is indicated by using the phrase evam rupah (“like this”-11:48). It was a furious form causing even a gallant person like Arjuna to tremble with fear.
Sanskrit
मया प्रसन्नेन तवार्जुनेदं रूपं परं दर्शितमात्मयोगात् ।
तेजोमयं विश्वमनन्तमाद्यं यन्मे त्वदन्येन न दृष्टपूर्वम् ॥ 11:47 ॥
Word Separation
मया प्रसन्नेन तव अर्जुन इदम् रूपम्
परम् दर्शितम् आत्म-योगात्; तेजः-मयम् विश्वम् अनन्तम्, आद्यम् यत् मे त्वत्-अन्येन न दृष्ट-पूर्वम्।