Prema-bhakti, as actually demonstrated by mother Yasoda.
Srila Prabhupada: In the beginning, the Vedic purpose is pursued in three ways (trayi) — by karma-kaṇḍa, jsana-kaṇḍa and upasana-kaṇḍa. When one reaches the complete, perfect stage of upasana-kaṇḍa, one comes to worship Narayaṇa, or Lord Viṣṇu. When Parvati asked Lord Mahadeva, Lord Siva, what is the best method of upasana, or worship, Lord Siva answered, aradhananaḿ sarveṣaḿ viṣṇor aradhanaḿ param. Viṣṇupasana, or viṣṇv-aradhana, worship of Lord Viṣṇu, is the highest stage of perfection, as realized by Devaki. But here mother Yasoda performs no upasana, for she has developed transcendental ecstatic love for Kṛṣṇa. Therefore her position is better than that of Devaki. In order to show this, Srila Vyasadeva enunciates this verse, trayya copaniṣadbhiḥ etc.