Reeves was educated at Great Yarmouth Grammar School,[5] served in the Great War[6] and Sidney Sussex College, Cambridge — he read history and moral science, graduated Bachelor of Arts (BA) in 1924 and proceeded Master of Arts (Cambridge) (MA Cantab) in 1943.

He then trained for the ministry at the College of the Resurrection, Mirfield and the General Theological Seminary, New York and was ordained into the Church of England: deaconed on Trinity Sunday 1926 (30 May)[7] and priested the next Trinity Sunday (12 June 1927) — both times by Arthur Winnington-Ingram, Bishop of London, at St Paul's Cathedral.

[1] Reeves' title post (curacy) was at St Albans, Golders Green (1926–1931), during which time he was also secretary of the theological department of the Christian Social Movement.

[11] He served as the third Bishop of Johannesburg (succeeding Clayton)[9] from his consecration[12] until 1961 – his position became untenable when the government of South Africa deported him on 12 September 1960[13] and he resigned the see effective 31 March 1961.

He served as general secretary of the Student Christian Movement (SCM), 1962–1965[6] (during which time he was also an Assistant Bishop of London until 1966.