इहैकस्थं जगत्कृत्स्नं पश्याद्य सचराचरम्। मम देहे गुडाकेश यच्चान्यद्द्रष्टुमिच्छसि ॥

ihaika-sthaṁ jagat kṛitsnaṁ paśhyādya sa-charācharam mama dehe guḍākeśha yach chānyad draṣhṭum ichchhasi

Here, to-day, behold the whole universe, movable and immovable, standing in one in My body, O Gudâkesha, with aught else thou desirest to see.

In plain words: Krishna tells Arjuna (here called Gudakesha, "one who has conquered sleep") to look at His body. The whole universe is there in one place, everything that moves and everything that stays still, plus anything else Arjuna wants to see.