Bhagavad Gita 18.20
सर्वभूतेषु येनैकं भावमव्ययमीक्षते। अविभक्तं विभक्तेषु तज्ज्ञानं विद्धि सात्त्विकम्।।18.20।।
sarvabhūteṣu yenaikaṃ bhāvamavyayamīkṣate| avibhaktaṃ vibhakteṣu tajjñānaṃ viddhi sāttvikam||18.20||
sarvabhuteshu yenaikam bhavamavyayamikshate avibhaktam vibhakteshu tajjnanam viddhi sattvikam18.20
Meaning
That knowledge by which one sees the one imperishable reality in all beings, undivided in the divided — know that knowledge to be sattvic.
जिस ज्ञान से मनुष्य, विभक्त रूप में स्थित समस्त भूतों में एक अविभक्त और अविनाशी (अव्यय) स्वरूप को देखता है, उस ज्ञान को तुम सात्त्विक जानो।
This is verse 20 of 78 in Chapter 18 (Moksha Sannyasa Yoga) of the Bhagavad Gita.