It is said, tretāyāṁ yajato makhaiḥ: in Tretā-yuga, if one performed yajṣas, he would get the results of those yajṣas. By performing viṣṇu-yajṣa specifically, one could even achieve the lotus feet of the Supreme Personality of Godhead. Of course, yajṣa is intended to please the Supreme Personality of Godhead. While Purūravā was meditating upon Urvaśī, the Tretā-yuga began, and therefore the Vedic yajṣas were revealed in his heart. But Purūravā was a materialistic man, especially interested in enjoying the senses. Yajṣas for enjoyment of the senses are called karma-kāṇḍīya-yajṣas. Therefore, he decided to perform karma-kāṇḍīya-yajṣas to fulfill his lusty desires. In other words, karma-kāṇḍīya-yajṣas are meant for sensuous persons, whereas yajṣa should actually be performed to please the Supreme Personality of Godhead. To please the Supreme Personality of Godhead in Kali-yuga, the saṅkīrtana-yajṣa is recommended. Yajṣaiḥ saṅkīrtana-prāyair yajanti hi sumedhasaḥ. Only those who are very intelligent take to saṅkīrtana-yajṣa to fulfill all their desires, material and spiritual, whereas those who are lusty for sense enjoyment perform karma-kāṇḍīya-yajṣas.