In December 1797 the Haldane brothers set up a society, consisting of Christians from all denominations, under the name of ‘The Society for Propagating the Gospel at Home.’ Their sole intention was to make known the Evangelical Gospel of our Lord Jesus Christ. James Haldane spent his time between tours evangelising the villages around Edinburgh, speaking to large crowds on Calton Hill and spending a lot of time studying the Bible. He was soon to add another occupation to these. His brother Robert, after having failed in his attempt to establish a great Indian mission, was now employed in the building of churches in order to help with the shortage in the cities, and the extension of evangelical religion at home. It was natural that in such a work he should seek the help of his brother. The Circus Church or Tabernacle as the first church was called, was in Edinburgh and could hold 2,500 people. The churches that Robert Haldane built were called Tabernacles after churches of the same name built by George Whitefield. On February 3rd, 1799, James Haldane was ordained as the minister of the first of his brother’s churches. The following extract from the account of James Haldane’s ordination will fully explain his views and purposes on becoming a minister. He "expressed his intention of endeavouring to procure a regular rotation of ministers to assist him in supplying the tabernacle. He declared his willingness to open his pulpit for the occasional labours of every faithful preacher of the Gospel, of whatever denomination or country he might be. He signified his approbation of the plan of the church which had chosen him for their pastor, as being simple and scriptural, but disavowed any confidence in it as a perfect model of a church of Christ, to the exclusion of all others. He wished to remember himself, and ever to remind his hearers, that the kingdom of heaven was not meat and drink, but righteousness, and peace, and joy in the Holy Ghost. Finally, he declared that he meant not to confine his exertions to that church, but to devote a portion of his time every year to the labours of itinerancy, to which he conceived himself, in the providence of God, to be especially called." He became the first minister of the first Congregational church in Scotland. By 1897 they numbered around 100 congregations
This is from an 1823 map found online at the National Library of Scotland. The Tabernacle is the shaded building on the south side of the High Street, in the middle of the map.