Bhagavatapurana 4.19.37

4.19.37

bhavān paritrātum ihāvatīrṇo dharmaṃ janānāṃ samayānurūpam /
venāpacārād avaluptam adya tad-dehato viṣṇu-kalāsi vainya //

37. Thou hast made an Avatāra here in order to protect Dharma among men according to the times—Dharma which has now declined on account of wickedness and fault of Vena; thou hast issued from his body and art a ray of Vishnu, O son of Vena.