ब्रह्म सर्वमिदं विश्वं विश्वातीतं च तत्पदम् ।वस्तुतस्तु जगन्नास्ति सर्वं ब्रह्मैव केवलम्
In plain words
Brahman is all this universe, and Brahman is that state which transcends the universe; but in truth the world does not exist at all — all is Brahman, and Brahman alone.