tÄv imau vai bhagavato
harer amÅ›Äv ihÄgatau
bhÄra-vyayÄya ca bhuvaḥ
kṛṣṇau yadu-kurūdvahau
tau - both; imau - these; vai - certainly; bhagavataḥ - of the Supreme Personality of Godhead; hareḥ - of Hari; amÅ›au - part and parcel expansion; iha - here (in this universe); Ägatau - has appeared; bhÄra-vyayÄya - for mitigation of the burden; ca - and; bhuvaḥ - of the world; kṛṣṇau - the two Kṛṣṇas (Kṛṣṇa and Arjuna); yadu-kuru-udvahau - who are the best of the Yadu and Kuru dynasties respectively.
NÄrÄyaṇa is the Supreme Personality of Godhead, and Nara is a part of the Supreme Personality of Godhead, NÄrÄyaṇa. Thus the energy and the energetic together are the Supreme Personality of Godhead. Maitreya informed Vidura that Nara, the portion of NÄrÄyaṇa, had appeared in the family of the Kurus and that NÄrÄyaṇa, the plenary expansion of Kṛṣṇa, had come as Kṛṣṇa, the Supreme Personality of Godhead, with the purpose of delivering suffering humanity from the pangs of material burdens. In other words, NÄrÄyaṇa Ṛṣi was now present in the world in the forms of Kṛṣṇa and Arjuna.