Gita Series – 119: Chapter - XI. Verse 5 – 9
Kṛṣṇa said, “Behold Arjuna, My innumerable and multifarious forms of Mine. Behold the twelve Āditya-s, the eight Vasu-s, the eleven Rudra-s, the two Aśvin-s, the forty nine Marut-s and many wonders that you have not seen before. Behold the essence of My entire creation, both animate and inanimate along with what you desire to see. But, Arjuna, you are incapable of seeing Me with your biological eyes. Therefore, I give you divine vision. With this, behold My divine yogic form.”
Sañjaya said, “O, king, having said this, Kṛṣṇa showed His cosmic form to Arjuna.”
The Lord asks Arjuna to concentrate on the vision that is going to be shown to him. Kṛṣṇa insists on Arjuna’s absolute attention because Arjuna will never have another opportunity to witness His cosmic form. As Kṛṣṇa Himself says, His Brahman form cannot be seen with normal eyes and one needs clairvoyant eyes to look at the Cosmic Form of the Brahman. The effulgence of the Brahman will blind the sensory eyes. Hence Kṛṣṇa says that He would give Arjuna the divine eyes to see His blazing Cosmic Form. Kṛṣṇa also gives a brief of what Arjuna is going to see in His cosmic form. Kṛṣṇa had in the earlier chapter already described about Āditya-s, Vasu-s, Rudra-s, Aśvin-s, Marut-s and others. What had been described earlier by Kṛṣṇa (chapter X. 21 and 23) is going to be seen by Arjuna as a miniscule part of His cosmic form. Kṛṣṇa says that Arjuna is going to witness several wonders in His cosmic form that Arjuna has not witnessed so far. The cosmic form of the lord is going to contain both movable and immovable, in accordance with His omnipresent nature.
Kṛṣṇa has thus given a briefing to Arjuna, as the Lord never wanted Arjuna to be in for shocks and surprises about His cosmic form. Thus, the Lord calibrates Arjuna’s mental condition. Kṛṣṇa now plays a dual role, one as Arjuna’s spiritual preceptor and another as the Supreme Lord.
Sañjaya tells his king Dhṛtarāṣtra (please refer Chapter I.1) that the Supreme Yogi, Lord Hari in the form of Kṛṣṇa revealed His Cosmic form to Arjuna.