CC Madhya 24.308

viṣṇu-śaktiḥ parā proktā
kṣetrajñākhyā tathā parā
avidyā-karma-saṁjñānyā
tṛtīyā śaktir iṣyate
Synonyms: 
viṣṇu-śaktiḥ — the potency of Lord Viṣṇu; parā — spiritual; proktā — it is said; kṣetra-jña-ākhyā — the potency known as kṣetrajña; tathā — as well as; parā — spiritual; avidyā — ignorance; karma — fruitive activities; saṁjñā — known as; anyā — other; tṛtīyā — third; śaktiḥ — potency; iṣyate — known thus.
Translation: 
“ ‘The potency of Lord Viṣṇu is summarized in three categories — namely the spiritual potency, the living entities and ignorance. The spiritual potency is full of knowledge; the living entities, although belonging to the spiritual potency, are subject to bewilderment; and the third energy, which is full of ignorance, is always visible in fruitive activities.’
Purport: 

This is a quotation from the Viṣṇu Purāṇa. For an explanation, see Ādi-līlā 7.119.