sa vā adhigato dadhyaṅṅ
aśvibhyāṁ brahma niṣkalam
yad vā aśvaśiro nāma
tayor amaratāṁ vyadhāt
saḥ—he; vā—certainly; adhigataḥ—having obtained; dadhyaṅ—Dadhyañca; aśvibhyām—to the two Aśvinī-kumāras; brahma—spiritual knowledge; niṣkalam—pure; yat vā—by which; aśvaśiraḥ—Aśvaśira; nāma—named; tayoḥ—of the two; amaratām—liberation in one’s life; vyadhāt—awarded.
That saintly Dadhyañca, who is also known as Dadhīci, personally assimilated the spiritual science and then delivered it to the Aśvinī-kumāras. It is said that Dadhyañca gave them mantras through the head of a horse. Therefore the mantras are called Aśvaśira. After obtaining the mantras of spiritual science from Dadhīci, the Aśvinī-kumāras became jīvan-mukta, liberated even in this life.
The following story is narrated by many ācāryas in their commentaries:
The great saint Dadhīci had perfect knowledge of how to perform fruitive activities, and he had advanced spiritual knowledge as well. Knowing this, the Aśvinī-kumāras once approached him and begged him to instruct them in spiritual science (brahma-vidyā). Dadhīci Muni replied, “I am now engaged in arranging sacrifices for fruitive activities. Come back some time later.” When the Aśvinī-kumāras left, Indra, the King of heaven, approached Dadhīci and said, “My dear Muni, the Aśvinī-kumāras are only physicians. Please do not instruct them in spiritual science. If you impart the spiritual science to them despite my warning, I shall punish you by cutting off your head.” After warning Dadhīci in this way, Indra returned to heaven. The Aśvinī-kumāras, who understood Indra’s desires, returned and begged Dadhīci for brahma-vidyā. When the great saint Dadhīci informed them of Indra’s threat, the Aśvinī-kumāras replied, “Let us first cut off your head and replace it with the head of a horse. You can instruct brahma-vidyā through the horse’s head, and when Indra returns and cuts off that head, we shall reward you and restore your original head.” Since Dadhīci had promised to impart brahma-vidyā to the Aśvinī-kumāras, he agreed to their proposal. Therefore, because Dadhīci imparted brahma-vidyā through the mouth of a horse, this brahma-vidyā is also known as Aśvaśira.
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