12th Ecumenical Council (Catholic reckoning) · Rome · A.D. 1215
The twelfth ecumenical council, the greatest of the medieval councils: it defined transubstantiation, required annual confession and communion, and issued seventy reforming constitutions and the crusade decree Ad liberandam.
Translated by Norman P. Tanner, Decrees of the Ecumenical Councils (Georgetown University Press, 1990). Source: papalencyclicals.net. In copyright; hosted freely at papalencyclicals.net.
Documents
- The Constitutions — Constitutions 1–70, with Tanner’s introduction — including constitution 1 on the Confession of Faith, which defines transubstantiation.
- Ad liberandam — The concluding crusade decree Ad liberandam (constitution 71), for the recovery of the Holy Land.