Born to a Christian family in Misozwe, Tanga, Edmund was the
last of five children. One of his elder brothers, John Sepeku, became the first
archbishop of what was then called the Church of the Province of Tanzania (now
the Anglican Church of Tanzania). He was educated at Misozwe, Kinanda, and Minaki.
He trained as a teacher and saw active service with the British army in Burma.
A career in the civil service followed, then a post in Radio Tanzania.
On July 9, 1967, Edmund had a vision in which he believed he was called to an active Christian ministry. He left his post with Radio Tanzania in mid 1968, and returned to Tanga. In June 1969 he prayed for a man named John who received healing for swollen leg. On reflection Edmund returned to Dar-es-Salaam, where he began an itinerant preaching ministry, which led to a call to start an Anglican congregation at Minyonyoni. The church exists to the present as the Church of St. John the Baptist.
The establishment of the church left Edmund free to begin an evangelistic ministry, preaching in beer clubs, visiting private homes, and praying for the sick and troubled. From this beginning grew the Huduma ya Nyumba kwa Nyumba (House to House Fellowship), as it is known today, which maintains the tradition of house to house visiting and praying for the sick and troubled. Patients were asked to repent of all sin, trust Jesus, pray, abstain from alcohol, tobacco, and witchcraft, and fast on Fridays. Meetings were first held in what was then the Cathedral of St. Nicholas at Ilala. This was later replaced by the regular Thursday night fellowship meetings. The meeting included the singing of spiritual songs (Tenzi), the reading of Scripture, prayers for repentance, intercession, and healing. The Fellowship remains ecumenical until this day (2009) and participants come from a variety of faiths and denominations. Some come to faith when they seek out the assistance of the ministry, and none are told to leave their denomination for another or to set up a new church. Members of the fellowship are encouraged to be the leaven in their own parishes and churches.
Edmund's ministry soon stretched beyond the diocese of Dar-es-Salaam. Meetings in Dar-es-Salaam were accompanied by recorded miraculous healings, and Edmund was asked to visit other dioceses, such as Masasi, Morogoro, Tanga (then part of the Diocese of Zanzibar and Tanga), Victoria, Nyanza, and Central Tanganyika. The efforts of spiritual rigor and travel took their toll and Edmund became seriously ill at the end of 1974. He had a vision of his death in mid 1975 and died in June of that year. Before his death, he passed the mantle of directing Nyumba kwa Nyumba to Cyprian Salu who continues to lead the fellowship at the time of writing (2009). Cyprian's son Thomas had been miraculously healed at the hands of Edmund.
Edmund left a major legacy in Tanzania and, in many ways, presented an acceptable variation of Uamsho (revival) to the high church diocese in that country which had been founded by the Universities' Mission to Central Africa. His spiritual rigor resonated with all that had been best, and sometimes neglected within that Anglo-Catholic tradition. His development of a fellowship which worked, and still works, to enhance the work of all traditions rather than build itself up at the expense of some is a remarkable example of how Christians from different traditions may find common ground. Moreover, his ministry provided a remarkable challenge to many expatriate priests and mission personnel to think outside the box of their own culturally mediated understandings of faith.
The ministry he founded continues to meet at Buguruni Malapa in Dar-es-Salaam every Thursday of the year (except Maundy Thursday).