Srimad-Bhagavatam: Canto 6 - Chapter 1 - Verse 19

Sanskrit:

इन्द्र उवाचअहो दानव सिद्धोऽसि यस्य ते मतिरीद‍ृशी ।भक्त: सर्वात्मनात्मानं सुहृदं जगदीश्वरम् ॥ १९ ॥

ITRANS:

indra uvācaaho dānava siddho ’siyasya te matir īdṛśībhaktaḥ sarvātmanātmānaṁsuhṛdaṁ jagad-īśvaram

Translation:

Indra said: O great demon, I see by your discrimination and endurance in devotional service, despite your dangerous position, that you are a perfect devotee of the Supreme Personality of Godhead, the Supersoul and friend of everyone.

Purport:

As stated in Bhagavad-gītā (6.22): “Established in Kṛṣṇa consciousness, one never departs from the truth, and upon gaining this he thinks there is no greater gain. Being situated in such a position, one is never shaken, even in the midst of the greatest difficulty.” An unalloyed devotee is never disturbed by any kind of trying circumstance. Indra was surprised to see that Vṛtrāsura, undisturbed, was fixed in devotional service to the Lord, for such a mentality is impossible for a demon. However, by the grace of the Supreme Personality of Godhead, anyone can become an exalted devotee (striyo vaiśyās tathā śūdrās te ’pi yānti parāṁ gatim). An unalloyed devotee is sure to return home, back to Godhead.