John Hobbs was born on 22 February 1800, at St Peter's, Thanet, Kent, England. He was the son of Elizabeth Palmer and her husband, Richard Hobbs, a coachbuilder and maker of agricultural implements, who had been welcomed into the Methodist Society by John Wesley. Hobbs learned his father's trades, and in September 1816 was admitted as a member of the Wesleyan Society, becoming a lay preacher in 1819.
Hobbs emigrated to Van Diemen's Land (Tasmania) at the age of 22, to work among the convicts. Samuel Marsden, chaplain of New South Wales, tried to recruit him for the Church Missionary Society, but at Nathaniel Turner's suggestion Hobbs offered himself as an artisan to the Wesleyan mission in New Zealand. With Samuel Marsden, Henry Williams, Nathaniel Turner, and their families, Hobbs sailed from Sydney on the Brampton, arriving at the Bay of Islands on 3 August 1823. Hobbs and Turner joined Samuel Leigh, William White and James Stack at the Wesleyan mission station at Kaeo, near Whangaroa Harbour. Leigh, the mission's founder, was ill, and departed with Marsden. Hobbs constructed mission premises and transported goods by boat, often demonstrating an ability to improvise. A skilful linguist (eventually he spoke nine languages), in 1825 he composed two hymns in Maori, and in 1826 attempted a translation of the Lord's Prayer.
The missionaries were often in danger from local Maori. In January 1827 the mission station, Wesleydale, was sacked and Hobbs returned to Sydney, where on 14 August 1827 he married Jane Broggref, of Thanet. They were to have nine children. He was ordained, and returned to New Zealand in October 1827 to spearhead the re-establishment of the Wesleyan mission, under the protection of Ngati Hao leader Patuone, on Hokianga Harbour.
In co-operation with Stack, Hobbs bought land for the mission at Mangungu. He constructed premises, preached and treated the sick. He became a noted horticulturist, planting orchards and gardens and giving numerous fruit trees to the Maori. Another Wesleyan missionary, William White, arrived in 1830 and tension developed between the two men. When White complained of Hobbs's absence from the station, Hobbs was reprimanded by the secretary of the Wesleyan Missionary Society, and he requested to be transferred.
John and Jane Hobbs sailed for Tonga on the New Zealander on 6 June 1833. For some five years Hobbs laboured in Tonga, using his medical skills. He quickly mastered the language, and printed a prolific amount of material for the missions. However, when Jane Hobbs became ill in February 1838, they were forced to leave Tonga. Hobbs saved the lives of all on board the ship on which they departed, when he repaired a leak, using part of an old boot.
Hobbs returned to New Zealand to find that White had been dismissed, and that he himself had been vindicated by the London Committee. In 1838 he rebuilt the Mangungu mission house after its destruction by fire. Hika Tawa, his personal assistant, became the Wesleyans' first convert, and many Maori were converted in the 1830s.
Prior to the signing of the Treaty of Waitangi in February 1840, Hobbs had lengthy discussions with his convert Tamati Waka Nene, whose speech turned the tide in favour of the treaty during the signing at Waitangi. At the Mangungu signing, Hobbs interpreted for Lieutenant Governor William Hobson. In 1847 he noted that he had translated Hobson's assurances that the Crown wanted sovereignty, not land, and that land would never be forcibly taken. During the northern war in 1845–46, he used his influence with a number of Hokianga chiefs to limit the spread of the fighting.
Hobbs undertook two epic journeys in connection with the Wesleyan mission. In 1839 with John Bumby, his superintendent, he carried out a survey of possible mission sites, visiting by ship East Cape, Port Nicholson (Wellington), Cloudy Bay, Kapiti, Taranaki and Kawhia, and travelled inland to mediate between warring tribes. He returned home from Kawhia, travelling on foot and by canoe. In 1848 he sailed to Wanganui to assist Emma, his daughter, and her husband, William Kirk, establish a mission station on the Wanganui River.
Suffering from rheumatism, and increasingly deaf, Hobbs left Hokianga for Auckland in 1855. An accomplished musician, he built at least two pipe organs. He never owned any land worth speaking of. Living a life of strict integrity and devotion to his church, he was intolerant of those with lesser standards. John and Jane Hobbs's eldest son, Richard, became a member of the House of Representatives, while a daughter, Marianne, married William Gittos and became a missionary at Kaipara. Hobbs died on 24 June 1883. He is buried in the Grafton cemetery, Auckland.