Purgatory

The noun purgatorium is no older than about 1170 to 1180, Jacques Le Goff argued in 1981; earlier writers spoke only of purgatorial fire or purgatorial places.

Jacques Le Goff, La Naissance du Purgatoire (1981), tr. Arthur Goldhammer, The Birth of Purgatory (University of Chicago Press, 1984), as summarised by Natalie Zemon Davis, New York Review of Books, 18 July 1985

In Catholic doctrine, a state of purification after death for souls on their way to heaven.

Sources4 sources

Primary source

Council of Trent, Session XXV, Decree concerning Purgatory, in The Canons and Decrees of the Sacred and Oecumenical Council of Trent, ed. and tr. J. Waterworth (London: Dolman), 1563, pp. 232-233 (Waterworth 1848)Trent's December 1563 decree: there is a purgatory and the souls detained there are helped by the suffrages of the faithful and principally by the sacrifice of the altar.
the souls there detained are helped by the suffrages of the faithful

Scholarship

Jacques Le Goff, The Birth of Purgatory, tr. Arthur Goldhammer (University of Chicago Press); French La Naissance du Purgatoire (1981), 1984Le Goff argues that Purgatory as a distinct place, and the noun purgatorium, appear in Latin theology only in the late twelfth century.
Natalie Zemon Davis, Happy Endings (review of Le Goff, The Birth of Purgatory), The New York Review of Books, 1985, 18 July 1985Confirms that Le Goff dates the coinage of the noun purgatorium to 1170 to 1180.
he gives a date (1170–1180) for the coinage of the noun purgatorium

The tradition itself

Edward Hanna, Purgatory, The Catholic Encyclopedia, vol. 12 (New York: Robert Appleton), 1911, section 'Errors'Purgatory is Catholic, not Orthodox, doctrine; the Greeks at Florence disputed purgatorial fire and the Reformers came to deny purgatory universally.
The modern Orthodox Church denies purgatory