[1] His father went to Australia from 1837 to 1841 where he served as Resident Manager of the South Australian Company, leaving his family in Edinburgh.

During his father's absence, Maclaren was converted and publicly baptized into the fellowship of the Hope St. Baptist Church, Glasgow, some time between age 11 and 13.

[1] During his ministry, the congregation built and relocated to Union Baptist Chapel, Oxford Road, Manchester, completed in 1869.

He visited Australia and New Zealand in 1889 where he preached at major cities to large congregations, despite poor health.

He said that few speakers had exceeded Maclaren "for profundity of thought, logical arrangement, eloquence of appeal, and power over the human heart".