Bg 10.27

uccaiḥśravasam aśvānāṁ
viddhi mām amṛtodbhavam
airāvataṁ gajendrāṇāṁ
narāṇāṁ ca narādhipam
Synonyms: 
uccaiḥśravasam — Uccaiḥśravā; aśvānām — among horses; viddhi — know; mām — Me; amṛta-udbhavam — produced from the churning of the ocean; airāvatam — Airāvata; gaja-indrāṇām — of lordly elephants; narāṇām — among human beings; ca — and; nara-adhipam — the king.
Translation: 
Of horses know Me to be Uccaiḥśravā, produced during the churning of the ocean for nectar. Of lordly elephants I am Airāvata, and among men I am the monarch.
Purport: 

The devotee demigods and the demons (asuras) once took part in churning the sea. From this churning, nectar and poison were produced, and Lord Śiva drank the poison. From the nectar were produced many entities, of which there was a horse named Uccaiḥśravā. Another animal produced from the nectar was an elephant named Airāvata. Because these two animals were produced from nectar, they have special significance, and they are representatives of Kṛṣṇa.

Amongst the human beings, the king is the representative of Kṛṣṇa because Kṛṣṇa is the maintainer of the universe, and the kings, who are appointed on account of their godly qualifications, are maintainers of their kingdoms. Kings like Mahārāja Yudhiṣṭhira, Mahārāja Parīkṣit and Lord Rāma were all highly righteous kings who always thought of the citizens’ welfare. In Vedic literature, the king is considered to be the representative of God. In this age, however, with the corruption of the principles of religion, monarchy decayed and is now finally abolished. It is to be understood that in the past, however, people were more happy under righteous kings.