During the period from 1954 to 1967 Gisbert attended University of Münster, Germany, and Pontifical Gregorian University in Italy, where he studied philosophy, theology and music.
Gisbert Greshake was ordained a Roman Catholic priest in 1960. The following year he started to serve at parishes in Dinslaken, Germany. Gisbert held the post of a priest till 1966, when he was appointed an assistant professor at University of Munster and Tubingen and held the position until 1973.
The following year Greshake accepted a post of a professor at University of Vienna, where he worked till 1985. He also acted as a dean of the Faculty of Theology at the same university during the period from 1979 to 1983.
Two years later Gisbert began to work as a professor at University of Freiburg in Germany.
Gisbert Greshake started to work as a visiting professor at the Pontifical Gregorian University in Rome in 1988, a post he held until 2006.