TRACTATUS CONTRA SACRA CONCILIA OF JAN BISKUPIEC. A NEW SOURCE FOR THE HISTORY OF POLISH ECCLESIOLOGY IN THE 15TH C

'Tractatus contra sacra concilia' is a work so far unknown to Polish and international historiography. Its author was Jan Biskupiec (c. 1377- 22 April 1452), a Polish Dominican, from 1417 the bishop of Chelm. The text of the treatise survived in one incomplete copy in Biblioteca de la Universidad de Salamanca, MS 2504, f. 258v-265v. The manuscript is a 15th c. codex which belonged to the Dominican John of Segovia. The treatise was written in Cracow, most probably between the second half or the end of 1440 and mid-1441. Its author condemns the schism made in 1439 by the Council of Basel, defends the rightful pope Eugene IV and presents a monarchic vision of the Church with the pope as its head, equipped with absolute power by the will of Christ himself. A critical edition of Polish translation is being prepared.