CC Madhya 19.165
brahmānando gurur api camatkārayaty eva tāvat
yāvat premṇāṁ madhu-ripu-vaśī-kāra-siddhauṣadhīnāṁ
gandho ’py antaḥ-karaṇa-saraṇī-pānthatāṁ na prayāti
There are different types of perfections known as siddhi-vraja, and also the perfections of achieving brahminical qualifications, yogic trance and merging into the Supreme. All these material perfections are certainly very attractive for a mundane person, but their brilliance exists only as long as one does not take to devotional service. Devotional service can control the Supreme Personality of Godhead, who is the supreme controller of all universal affairs. The five rasas (mellows) in the transcendental world are practiced by the inhabitants of Goloka Vṛndāvana in neutrality, servitorship, friendship, parental affection and conjugal love. All these please the Lord so much that He is controlled by the devotees. For instance, mother Yaśodā was so advanced in devotional service that Kṛṣṇa agreed to be controlled by her stick. In other words, the five principal mellows are so great and glorious that they are able to control the Supreme Personality of Godhead. In the material world, however, the so-called siddhis, or perfections, manifest their brightness only as long as one is not interested in devotional service. In other words, the perfection of the karmīs, jñānīs, yogīs and others remains attractive only as long as one does not come to the point of devotional service, which is so great and significant that it can control the supreme controller, Kṛṣṇa.