The Reverend Jabez Waters Sims was born on 13 November 1831, the eldest child of a tailor of Basingstoke, Hampshire, England, Jabez Sims (d.1849), and his wife Susannah (née Waters). He became a schoolmaster. At Tickenham (near Bristol) on New Year's Day 1851, at the age of 19, he married Mary Ann Gladwin (b.1833) of Portbury, Somerset. After teaching for a while at Chepstow, Monmouthshire, he emigrated with his family to New Brunswick at some time after the spring of 1854. In 1857 he moved to Glen Williams, Canada West. There he gave gratuitous assistance in his ministry to the Reverend J.G.D. McKenzie. Benjamin Cronyn, the first Bishop of Huron, ordained him to the deaconate on 28 October 1862 and to the priesthood on 28 October 1863. From January 1863 to October 1864 he served as a missionary at Dungannon and parts adjacent in Huron County, and as Superintendent of Schools for the Townships of Ashfield, Colborne and Wawanosh.

After studing the Ojibway language under the Reverend Dr. Frederick A. O'Meara, a former missionary on Manitoulin Island, he took over the mission in that island in October 1864. There the Indians gave him the name of Muckadez Cunesse (Little Blackcoat). In 1868 he moved the mission's headquarters from Manitowaning to Sheguiandah. On the 18 August 1869, while travelling with his family to Killarney to baptize a child, he was drowned, and was buried in a corner of this own garden because there was no burial ground at Sheguiandah. He left a young family of five surviving sons and one daughter.