The Curia Christi ("Court of Christ") or Curia Dei ("Court of God") was a diet or court day (Hoftag) of the Holy Roman Empire held in Mainz on 27 March 1188. It was so called because it was notionally under the presidency of Jesus Christ as king of kings. It was the occasion both for the public resolution of the conflict between Emperor Frederick Barbarossa and Archbishop Philip of Cologne and for the emperor's "taking of the cross", when he vowed to lead an army on the Third Crusade.