Bhagavatapurana 3.29.11

3.29.11

mad-guṇa-śruti-mātreṇa mayi sarva-guhāśaye /
mano-gatir avicchinnā yathā gaṅgāmbhaso 'mbudhau //

11—12. The disinterested and immediate devotion to Me, the Purushottama, abiding in the hearts of all, which takes the form of the mind’s uninterrupted thought (of Myself) flowing towards Me like the waters of the Ganga towards the sea, at the very moment when My excellent attributes, are heard,—that devotion is, it is said, the characteristic of the Bhakti-yoga which is said to be Nirguna. [Note:—The Bhakti spoken of in the verses 8 to 10 is said to be Saguna Bhakti yoga having 81 varieties.]