GROPPER, JOHANN. - Theologian and jurist, b. at Soest (Westphalia) on 24 Feb. 1503, d. at Rome on 13 March 1559. After completing his studies at Cologne, he held various important offices, among them those of chancellor of the episcopal principality, scholasticus of St. Gereon, dean in Soest and, from 1547, provost and archdeacon of Bonn.
Codifier of the law of the ecclesiastical principality of Cologne and compiler of the decrees of the provincial Synod of 1536, through intelligent and courageous action he was able to oppose the machinations of the apostate archbishop Hermann von Wied, saving Catholicism in Cologne. In the religious controversies he represented the moderate tendency, by which he was inspired in the diets and colloquies in which he took part: Augsburg (1530), Hagenau, Worms (1540), Regensburg (1541) and in the Interim of Augsburg (1548), of which he was the principal draftsman. His doctrine on the duplex iustitia was rejected by the Council of Trent (1546). In 1551 he accompanied Archbishop Adolph von Schauenburg to Trent. He firmly refused the purple, to which Paul IV wished to raise him in 1555. In 1558, fearing that the archbishop of Cologne Gebhard von Mansfeld was of doubtful orthodoxy, he went to Rome to prevent his confirmation; on that occasion he had to defend himself against the accusation of dogmatic errors, but this did not deprive him of the Pope's trust, for the Pope used him as a counselor and extolled his virtues in the funeral eulogy that he delivered on the occasion of his burial in the church of S. Maria dell'Anima.
Works: Canones Concilii provincialis Coloniensis, with the Enchiridion appended (Cologne 1538); Antididagma (ibid. 1544); Wahrhaftige Antwort und Gegenberichtung (ibid. 1545); Capita institutionis ad pietatem, (ibid. 1546); Von warer Gegenwertigkeit des Leyds und Bluts Christi (ibid. 1548); Institutio Catholica (ibid. 1550).
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