KAIVALYA UPANISHAD · 10

सर्वभूतस्थमात्मानं सर्वभूतानि चात्मनि ।
सम्पश्यन्ब्रह्म परमं याति नान्येन हेतुना ॥ १०॥

sarvabhūtasthamātmānaṃ sarvabhūtāni cātmani ।
sampaśyanbrahma paramaṃ yāti nānyena hetunā ॥ 10॥

He only attains Parabrahman who sees in himself all elements and himself in all elements. There is no other means.

K. Narayanasvami Aiyar · Thirty Minor Upanishads (1914), pp. 31–33