He was a son of customs officer Joseph Frantz Oscar Michelet (1832–1913) and Caroline Julie Laache (1833–1915).
On the maternal side he was a first cousin of doctor and professor of medicine, Søren Bloch Laache (1854-1941).
He also taught at Aars og Voss skole and Trondhjem Cathedral School from 1887 to 1888.
He studied in Leipzig; first history of religion and Indian languages, then the theology of the New Testament.
[4] He worked as a teacher and priest until being appointed as a professor of theology at the University of Kristiania in 1896.
He was decorated as a Knight, First Class of the Order of St. Olav in 1911, and died in October 1942 in Bærum Municipality.