Śrī Venkateśvara
Tirumala is the 108th and most celebrated of the 108 Divya Desams. The presiding deity is Śrī Venkateśvara (also called Śrīnivāsa, Bālājī, Tiruvēṅkaṭamuḍaiyān, Kalyāṇa Perumāḷ) — Viṣṇu in his sthānaka (standing) form on the sacred Śeśāchala hills. Nammāzhvār and Tirumaṅkai Āzhvār sang of him in the Divya Prabandham.
The Tirumala Hills
The seven hills of Tirumala are identified with the seven hoods of Ādiśeṣa — the Lord rests on Śeṣa in Vaikuṇṭham, and here at Tirumala, the hill itself is Śeṣa, and the Lord rests on it. This is why Tirumala is sometimes called Śeṣādri (the hill of Śeṣa).
Miracles and Grace
Numerious theological stories surround Tirupati's grace: Śrī Venkateśvara is said to have taken a loan of gold (vaiśya motif) to fund his marriage with Padmāvatī (Lakṣmī). Devotees offer gold, hair (tonsure), and vast wealth as repayment of their own debt to the Lord for the grace received. The vast haundi (offering box) receives millions of rupees and kilograms of gold daily.
Vaikhānasa Tradition
Tirumala follows the Vaikhānasa āgamic tradition (unlike most Divya Desams which follow Pañcarātra). The priests are exclusively Vaikhānasa Brahmins trained in this ancient tradition.