Bhagavatapurana 3.29.2

3.29.2

yathā sāṅkhyeṣu kathitaṃ yan-mūlaṃ tat pracakṣate /
bhakti-yogasya me mārgaṃ brūhi vistaraśaḥ prabho //

1 & 2. The description of the Mahat Tattva and other principles of Prakriti and Purusha has been given as known to the Sankhyas—the description by which their true and distinct nature is perceived and which is said to be the source of the Bhakti-yoga; be pleased to describe to me that Bhakti-yoga in detail, O Lord.