As stated in Bhagavad-gītā (7.16), catur-vidhā bhajante māṁ janāḥ sukṛtino ’rjuna. Without sukṛti, or pious activities, no one can come to the shelter of the Supreme Personality of Godhead. The Lord is approached by four kinds of pious men (ārto jijñāsur arthārthī jñānī ca), but here we see that Nanda Mahārāja and Yaśodā surpassed all of them. Therefore Parīkṣit Mahārāja naturally inquired, “What kind of pious activities did they perform in their past lives by which they achieved such a stage of perfection?” Of course, Nanda Mahārāja and Yaśodā are accepted as the father and mother of Kṛṣṇa, yet mother Yaśodā was more fortunate than Nanda Mahārāja, Kṛṣṇa’s father, because Nanda Mahārāja was sometimes separated from Kṛṣṇa whereas Yaśodā, Kṛṣṇa’s mother, was not separated from Kṛṣṇa at any moment. From Kṛṣṇa’s babyhood to His childhood and from His childhood to His youth, mother Yaśodā was always in association with Kṛṣṇa. Even when Kṛṣṇa was grown up, He would go to Vṛndāvana and sit on the lap of mother Yaśodā. Therefore there is no comparison to the fortune of mother Yaśodā, and Parīkṣit Mahārāja naturally inquired, yaśodā ca mahā-bhāgā.