SB 3.8.26

He saw the Lord mercifully showing one lotus foot which fulfills the desire for service for persons who worship to attain the Lord by pure methods of bhakti, whose toes were like beautiful petals blossoming in the moon rays of his toe nails. He saw the lotus feet which were fulfilling desires of those who worship on special paths, for fulfilling their desires (sva-kāmāya), or with a desire for attaining the Lord (sva), or for satisfying the Lord with service. Vivikta-mārgaiḥ means “by paths which were not mixed with jṣāna or karma.” Or it can mean “by pure paths, arising from vaidhi or rāgānuga-- bhāva-marga with dāsya, sakhya or other rasas.” Those feet fulfilled the desires for serving properly (kāma-dugha). He showed only one foot among many thousands of his feet, by lifting it up slightly. By this hint and moving one eyebrow in the next verse, it is indicated the Lord showed his form as Kṛṣṇa (though Kṛsṇa appears only later during Vaivasvata Manvantara) to Brahmā in this and the next two verses. Other scriptures also indicate that Kṛṣṇa revealed himself to Brahmā. Tad u hovāca brāhmaṇo sadanaṁ carato me dhyātaḥ stutaḥ parārddhānte so ’budhyata gopaveśo me purastāt āvirbabhūva; after passing the first half my lifetime, when the night ended, I and meditated and praised the Lord, who appeared in the dress of a cowherd boy before me. (Gopala-tāpanī Upaniṣad) Brahma-saṁhitā also describes how Kṛṣṇa showed himself to Brahmā. Thus some say that “revealing one foot” in this verse refers to the form of Kṛṣṇa, who stands with his feet crossed, showing one sole of his foot. His toes were like graceful petals opened by the rays from his moon-like toe nails. What is astonishing here is that the lotus is blossoming in the moonlight instead of the sunlight.