Bhagavad Gita · 11.9

सञ्जय उवाचएवमुक्त्वा ततो राजन्महायोगेश्वरो हरिः।दर्शयामास पार्थाय परमं रूपमैश्वरम्॥

sañjaya uvācha evam uktvā tato rājan mahā-yogeśhvaro hariḥ darśhayām āsa pārthāya paramaṁ rūpam aiśhvaram

Sanjaya said: O King, having spoken thus, the great Lord of Yoga, Hari, then revealed to Arjuna his supreme divine form.

— Bhagavad Gita 11.9

Source: Sacred-Texts.com (Sanskrit) + Bhagavad-Gita.io (translations)