dhanur viyati māhendraḿ
nirguṇaḿ ca guṇiny abhāt
vyakte guṇa-vyatikare
'guṇavān puruṣo yathā
dhanuh -- the bow (rainbow); viyati -- within the sky; maha-indram -- of Lord Indra; nirgunam -- without qualities (or without a bowstring); ca -- although; gunini -- within the sky, which has definite qualities like sound; abhat -- appeared; vyakte -- within the manifest material nature; guna-vyatikare -- which consists of the interactions of material qualities; aguna-van -- He who has no contact with material qualities; purushah -- the Supreme Personality; yatha -- just as.
Srila Prabhupada comments as follows: "Sometimes, in addition to the roaring thunder of the clouds, there is an appearance of a rainbow, which stands as a bow without a string. Usually, a bow stays in the curved position because it is tied at its two ends by the bowstring; but in the rainbow there is no such string, and yet it rests in the sky so beautifully. Similarly, when the Supreme Personality of Godhead descends to this material world, He appears just like an ordinary human being, but He is not resting on any material condition. In the Bhagavad-gita, the Lord says that He appears by His internal potency, which is free from the bondage of the external potency. What is bondage for the ordinary creature is freedom for the Personality of Godhead."