Shastriji Maharaj (Gujarati: શાસ્ત્રીજી મહારાજ) (31 January 1865 – 10 May 1951), born Dungar Patel and ordained Shastri Yagnapurushdas, was the third spiritual successor of Swaminarayan in the BAPS Swaminarayan Sanstha. Born in a family of farmers in central Gujarat, India, he became a sadhu within the Vadtal diocese of the Swaminarayan Sampraday at the age of 17 where he was given the name Yagnapurushdas Swami. The prefix Shastri was later added in recognition of his eminent scholarship in Sanskrit and the Hindu scriptures. He established and nurtured a nascent BAPS after a doctrinal split from the Vadtal diocese of the Swaminarayan Sampradaya.
Shastriji Maharaj is credited with establishing BAPS on 5 June 1907 CE in Bochasan, Gujarat to propagate the Akshar-Purushottam Upasana (philosophy), which, he explained, had been revealed by Swaminarayan. A staunch proponent of this philosophy, he consecrated the sacred images of Swaminarayan (as a manifestation of Purushottam) and Gunatitanand Swami (as a manifestation of Akshar) in the central shrines of major mandirs in the towns of Bochasan, Sarangpur, Atladra, Gondal and Gadhada in Gujarat, India.