He was born at Bridge of Earn, Perthshire, and educated at the University of St Andrews and University of Edinburgh. In 1845 he became minister of St Paul's, Dundee, and in 1849 of Kettins, in Strathmore, where he remained for six years. In 1854 he was appointed principal of St Mary's College, St Andrews. The appointment was immediately followed by the appearance of his Burnet prize essay on Theism. At St Andrews, where he was also professor of systematic theology and apologetics, his teaching was distinguished by several novel features. He lectured on comparative religion and treated doctrine historically, as being not a fixed product but a growth.
He quickly won the attachment and admiration of his students. In 1862 he was appointed a clerk of the General Assembly, and from then on he took a leading part in the councils of the Church of Scotland. In 1878 he was chosen moderator of the Assembly, and did much to widen the national church. Two positions on which he repeatedly insisted took a firm hold--first, that a church must be comprehensive of various views and tendencies, and that a national church especially should seek to represent all the elements of the life of the nation; secondly, that subscription to a creed can bind no one to all its details, but only to the sum and substance, or the spirit, of the symbol.
For three years before his death he was convener of the church interests committee of the Church of Scotland, which had to deal with a great agitation for disestablishment. He was also deeply interested in the reorganization of education in Scotland, both in school and university, and acted as one of the temporary board which settled the primary school system under the Education Act of 1872. He died at Torquay.
Tulloch's best-known works are collections of biographical sketches of the leaders of great movements in church history, such as the Reformation and Puritanism. His most important book, Rational Theology and Christian Philosophy (1872), is one in which the Cambridge Platonists and other leaders of dispassionate thought in the 17th century are similarly treated. He delivered the second series of the Croall lectures, on the Doctrine of Sin, which were afterwards published. He also published a small work, The Christ of the Gospels and the Christ of History, in which the views of Ernest Renan on the gospel history were dealt with; a monograph on Blaise Pascal for Blackwood's Foreign Classics series; and a little work, Beginning Life, addressed to young men, written at an earlier period.
A biography of Tulloch was written by Mrs Oliphant.
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