Taking a keen interest in the local Independent Chapel, he became an early Sunday school teacher, and in 1792 decided to give up law and train full-time as a minister at Hoxton College near London.
In 1797 he settled close to London in the village of Walthamstow in Essex to carry out pastoral duties, becoming the minister of Marsh Street Congregational Chapel, in whose grounds he was buried in 1847.
Detached from Hoxton, he was sought after by other educationalists, and was attracted to an offer to become the founding President and first tutor of a new theological institution, the Hackney Academy.
In 1822 he gave evidence against James Hamilton, a local painter and decorator who had returned to george Collisons house and college after carrying out refurbishments, to steal Isaac Phillips' purse containing fifty sovereigns.
His close links to wealthy City Congregationalists, and to Congregational Ministers, also enabled him to form an unusually like-minded group of backers to launch and finance the venture.
More directly, in 1840, George Collison himself wrote that: 'Mount Auburn, near Boston... may be considered a kind of prototype of the rest, is an object of transcendent interest to the traveller, and, is in a great degree similar to our own cemetery at Abney Park'.
This remark about the weight Collison accorded to Mount Auburn Cemetery, together with Collison's wider cemetery studies, were collated and published in his methodical review and reflection entitled: This learned volume set out a meticulous listing of all the trees and shrubs commissioned for the Abney Park A to Z Arboretum, and for ornamental beds around the chapel, and for its rosarium of over one thousand cultivars, varieties and species; together with a potential design for a monument to commemorate the life of Dr Isaac Watts whose association with the Abney estate had been a principal motivation for Collison's commercial cemetery scheme, which appears to an extent to have become a vehicle to finance the preservation of, and public access to, the revered Abney Park.
George Collison II was a keen promoter of there being a commemorative statue to Isaac Watts in London, and helped establish a committee to take the idea forwards.