SARDŪL SIṄGH GIĀNĪ, BHĀĪ (d.1913), the eldest son of Giānī Giān Siṅgh of Amritsar and a grandson of Giānī Bishan Siṅgh, was a noted Sikh scholar of his time. The family lived near Chowk Bābā Aṭal in a street still known as Galī Giānīāṅ, the street of the Giānīs. Bishan Siṅgh's samādh used to be behind Gurdwārā Bābā Aṭal of which shrine he is believed to have been officially a priest. The adjunct Giānī, meaning a priest as well as an expounder of sacred texts, thus passed on to the names of the male members of the family. Giānī Giān Siṅgh became the first secretary of the Siṅgh Sabhā established in Amritsar in 1873. Sardūl Siṅgh inherited the family's interest in Sikh learning. One of the aims of the Siṅgh Sabhā was to research and rewrite Sikh history. Under the aegis of the Siṅgh Sabhā, scholars from Amritsar and other places used to assemble for discussions at Māñjī Sāhib within the precincts of the Darbār Sāhib. The very first question at the very first such meeting was raised by Bhāī Sardūl Siṅgh, who held forth that the birth anniversary of Gurū Nānak fell on the third day of the light half of the month of Baisākh and not on full-moon day of the month of Kārtik as commonly believed. It was as a result of such scholarly discussions spreading over three years that a Gur Praṇāli, or calendar of the dates of the Gurūs, was compiled. A poetic version of it prepared by Bhāī Sardūl Siṅgh Giānī, was first published in a magazine, Mastānā, in 1936.

        Bhāī Sardūl Siṅgh was an active member of the Gurmat Granth Prachārak Sabhā set up on 8 April 1885 to study the Sikh texts, historical as well as religious. A theme which was entrusted to the Prachārak Sabhā by the Khālsā Dīwān, Amritsar, and in which he became deeply involved, was an exploration of the bāṇī or poetic works of Gurū Gobind Siṅgh, and to prepare an authorized version of the Dasam Granth. Summing up a protracted debate, Bhāī Sardūl Siṅgh prepared two reports, namely, Report Sodhak (Revision) Committee, Dasam Pātshāhī, Srī Gurū Gurmat Granth Prachārak Sabhā and Report Dasam Granth dī Sudhāī Dī, or report on revision of the Dasam Granth. The complete report was published in February 1898.

         Bhāī Sardūl Siṅgh was one of those learned Sikhs who assisted Max Arthur Macauliffe in his work on Sikh religion. He had some knowledge of English, too, and he taught Punjabi to several of the British officers posted at Amritsar. His own writings, comprising 22 titles, are all in Punjabi. They broadly fall into two categories; biographies of the Gurūs and expository essays on Sikhism. Not all of these works were published during the author's lifetime. Among those which were may be counted Gurisikkhāṅ de Nitya Karam (1885), or the daily duties of the Sikhs and Yātrā Abchalnagar (1897), a travelogue of the author's pilgrimage to Nāndeḍ, both published by the Gurmat Granth Prachārak Sabhā. A collection of his essays entitled 52 Lekchars, discourses delivered at Gurdwārā Bābā Aṭāl Sāhib, ran into several editions; its first edition under the title Gurmat Sambandhī Viākhiān was published by Wazīr Hind Press in1904 and its tenth edition is dated 1938. Gurū Prīkhyā, or the Gurū's Test, a 40-page pamphlet again published by the Prachārak Sabhā, refutes the charge that Gurū Gobind Siṅgh ever worshipped any goddess, and asserts the sovereignty of the Khālsā. Twenty three eminent persons and priests of the Harimandar, the Akāl Takht and the Darbār Sāhib, Tarn Tāran, are signatories to the document attesting the correctness and authenticity of the meaning of Gurū Gobind Siṅgh's stanza on which the author has based his thesis.

        In 1897, Bhāī Sardūl Siṅgh Giānī was given charge of the Sārāgaṛhī shrine at Amritsar where he passed the rest of his days. In December 1908, he was involved in a serious accident in which his tonga overturned as a result of which he sustained serious injuries and remained in a coma for a whole week. He survived the mishap only to suffer another tragedy, the sudden death of his only son, Darbārā Siṅgh, on Māgh sudī 4, 1965 Bk/ 25 January 1909. The bereaved father himself expired exactly four years later to the day, Māgh sudī 4, 1969 answering to 10 Feburary 1913.