References to Vāsudeva also occur in early Sanskrit literature. Taittiriya Aranyaka (X, i,6) identifies him with Narayana and Vishnu. Pāṇini, ca. 4th century BCE, in his Ashtadhyayi explains the word Vāsudevaka as a Bhakta (devotee) of Vāsudeva. At some stage during the Vedic period, Vasudeva and Krishna became one deity or three distinct deities Vasudeva-Krishna, Krishna-Gopala and Narayana, all become identified with Vishnu. and by the time of composition of the redaction of Mahabharata that survives till today.