“Kruthethu Naarasimho Bhoo Trethayaam Raghunandana
Dwapare Vasudevascha Kalau Venkatanayaka!” ||
Translation: In Kritha Yuga, Lord Narasimha, In Treta Yuga Lord Sri Rama, In Dwapara Yuga Lord Sri Krishna, and in Kaliyuga Lord Sri Venkateswara are called as Prathyaksha Dhaivams (Deities).
Sri venkatesa mahatyam (History & glories of Lord Venkatesha & Tirumala) is mentioned in Varaha Purana. According to the Varaha Purana, Adi Varaha manifested Himself on the western bank of the Swami Pushkarini, while Vishnu as Venkateswara came to reside on the southern bank of the Swami Pushkarini.
“Venkatesha Ashtottara namavali” which is 108 names of Lord Venkatesha is mentioned in Varaha Purana (this is different from 108 names mentioned in Brahmanda Purana), which is recited in Tirumala temple during morning pooja after second bell. According to the Varaha Purana, Lord Adi Varaha swami manifested Himself on the western bank of the Swami Pushkarini, while Lord Vishnu as Lord Venkateswara came to reside on the southern bank of the Swami Pushkarini.
“SrI: VenkatEsAth ParO dEvo nAsthyanya: SaraNam bhuvi
VenkatEsa SamO dEvo nAsthi nAsthi maheetaLE” –
–VarAha PurANam, First Canto
Meaning: There is no other God like VenkatEsa(sriman-Narayan) to seek refuge for protection and there is no other God equal to Lord Venkateshwara(sriman Narayan).