विष्णुरेव हि यस्यैष देवता वैष्णवः स्मृतः ॥
viṣṇur eva hi yasyaiṣa devatā vaiṣṇavaḥ smṛtaḥ ||
(Liṅga Purāṇa; cited in Hari-bhakti-vilāsa: 10.4)
“One whose devatā [i.e., cherished object of worship] is specifically Viṣṇu is known as a Vaiṣṇava [i.e., a bhakta of Viṣṇu].”