He started a careful study of the Bible during his voyages, and also came under the evangelical influence of David Bogue of Gosport, one of the founders of the London Missionary Society.

In about 1796 he became acquainted with the celebrated evangelical, Charles Simeon of Cambridge, in whose company he toured Scotland, distributing tracts and trying to awaken others to an interest in religious subjects.

Around 1815 he moved to the city centre, living at 16 George Street[5] and began preaching at the huge Tabernacle Church at the head of Leith Walk (now the site of the Playhouse Theatre).

The Haldanes also operated a seminary and were influenced in their principles by other independency thinkers such as John Glas and Robert Sandeman of the Glasite church.

As advancing years compelled him to withdraw from the more exhausting labours of travel and open-air preaching, he sought to influence the discussion of current religious and theological questions by means of the press.

[7] He died on 8 February 1851 aged 82, and is buried in the Haldane family plot in St Cuthbert's Churchyard at the west end of Princes Street in Edinburgh.