Sankaracarya's Vivekachudamani 470

निर्गुणं निष्कलं सूक्ष्मं निर्विकल्पं निरञ्जनम् ।

एकमेवाद्वयं ब्रह्म नेह नानास्ति किंचन ॥ ४६८ ॥

nirguṇaṃ niṣkalaṃ sūkṣmaṃ nirvikalpaṃ nirañjanam |

ekamevādvayaṃ brahma neha nānāsti kiṃcana ||

(Sankaracarya's Vivekachudamani 470)

With no qualities or parts, It is subtle without disturbances and taint-less--there is only the Brahman; one without a second; in it there is no duality whatsoever.

The word Brahman means "the greatest," and when we speak of the greatest we immediately refer to the Supreme Personality of Godhead, the source of all emanations. Unless the greatest possesses six opulence in full, he cannot be called the greatest. The greatest, who is full in six opulences, is the Supreme Personality of Godhead. In other words, the Supreme Brahman is the Supreme Personality of Godhead as well.

The Lord is always full in six opulence, as mentioned herein: wealth, renunciation, fame, knowledge, strength, and beauty. The word pūrtam means "in full." No one can claim that all wealth belongs to him, but Kṛṣṇa can claim it, since He has full wealth. Similarly, He is full of knowledge, renunciation, strength, and beauty. He is full in everything, and no one can surpass Him. Another one of Kṛṣṇa's names is asamaurdhva, which means that no one is equal to or greater than Him. (Srimad Bhagavatam------3:24:32)