His father, Alexander Pitcairn, was a merchant in Leith and Edinburgh, and was an elder in Lady Glenorchy's Chapel, where Dr Jones ministered as pastor for more than fifty years.

A Convocation was held at Edinburgh, on 17 November 1842, at which all those ministers who later left the established church were present, more than four hundred and fifty.

When, next year, the Disruption did take place, Pitcairn was again chosen, along with Patrick Clason of Edinburgh, to the Clerkship of the Free Church General Assembly.

When the Commission of the Free Church Assembly met in March following, they recorded "the affectionate respect entertained for their departed brother;" saying "that, in no small measure, the Free Church has been indebted to him for much of what is good in the tone and character of the proceedings of her supreme court, and in the general conduct of her ecclesiastical affairs.

[1][3] He married, 7 June 1836, his cousin, Ann Hay (died 28 April 1862),[3] daughter of Young Trotter of Cruicksfield, Berwickshire and had issue —