BG Chap 11 - The unique universal form showed to Arjuna by Kṛṣṇa
Arjuna had requested to see the universal form of the Lord. Being pleased with Arjuna’s devotion, Kṛṣṇa showed him the supreme, brilliant, infinite and original form of the universe, never before seen by anyone else. This form is situated within Kṛṣṇa, and like an actor or the vaidūrya gem, Kṛṣṇa can show many forms and colors. Arjuna could not see the form previously because yoga-māyā covered his vision.
In an attempt to avoid the Battle of Kurukṣetra, Mahārāja Yudhiṣṭhira sent Kṛṣṇa to Duryodhana as a messenger of peace. Duryodhana’s and Karṇa’s response, however, was foolish. To express disdain for the Pāṇḍavas’ strength, they plotted to bind Kṛṣṇa with ropes and throw Him into prison. Only a great devotee such as Yaśodā-devī, however, can evoke submission from the unlimitedly powerful Lord and bind Him. Binding Kṛṣṇa was impossible for Duryodhana because he was envious and devoid of bhakti. Duryodhana’s and Karṇa’s attempt only caused Kṛṣṇa to laugh and say, “You cannot bind Me. I exist everywhere!” At that time, Kṛṣṇa showed part of His universal form to Duryodhana, who became frightened but remained unsubmissive. Duryodhana continued minimizing Kṛṣṇa, despite His show of power, by saying, “Oh, Kṛṣṇa simply has mystic powers.” This universal form neither had the same effulgence nor possessed the kāla feature that Kṛṣṇa showed Arjuna.