Original sentence: In 1576 he established the Ostroh Academy, a regarded humanist educational and scholarship institution, with the instruction in Greek, Latin and Old Church Slavonic languages.In 1581 the Academy produced and published the Ostrog Bible, the first complete printed edition of the Bible in Old Church Slavonic.Prince Ostrogski was of Eastern Orthodox faith and he was active in supporting the illegal Orthodox Church (see Union of Brest) and, yet before that, promoting the Eastern culture in the Polish–Lithuanian Commonwealth.While Konstanty Wasyl Ostrogski was the proponent of the Eastern Orthodox religion, his son Janusz-Ivan converted to Roman Catholicism
Edited sentence: In 1576 he established the Ostroh Academy, a highly regarded humanist educational and scholarship institution, with the instruction in Greek, Latin and Old Church Slavonic languages.In 1581 the Academy produced and published the Ostrog Bible, the fundamental Orthodox Bible.Prince Ostrogski was of Eastern Orthodox faith and he was active in protecting the rights of the Orthodox Church (see Union of Brest) and promoting the culture of the Christian Orthodox religion in the Polish–Lithuanian Commonwealth.While Konstanty Wasyl Ostrogski was the guardian of the Eastern Orthodox religion, ironically, his son Janusz-Ivan converted to Catholicism