Six years after arriving in South Africa, John Bennie married Margaretha Magdalena Marè (1801–1868) from Graaf Reinet.

Four of his children were known to have been educated at Lovedale and his one son, John Angell became the boarding master and acting principal of the school after first teaching at another mission station for two years.

[5] On 18 November 1824 Bennie announced to his Presbytery that he was going to compile an extended list of vocabulary and grammar dealing mainly with pronunciation of the Xhosa language.

Through the Lovedale Mission Press he was able to publish a number of vocabulary lists as well as publications on grammar dealing with pronunciation.

John Bennie also was involved in translating and transcribing the oral narrative of a Xhosa convert from the Tyhume mission, known as Noyi or, after baptism, Robert Balfour.