Andrew Frycz Modrzewski (1503-1572) was educated at the universities of Cracow and Wittenberg, and at the latter institution he became intimately acquainted with Melanchthon. On his return to Poland he became secretary to Prince Sigismund Augustus. In 1546 he joined the Cracow circle of humanistic religious reformers, to which belonged Andrew Trzycieski, a fellow student of Modrzewski at Cracow, the publisher Wojewódka, the jurist James Przyłuski, James Uchański, deacon of the Cathedral Chapter, later archbishop and primate of Poland, Zebrzydowski, also deacon of the Cathedral Chapter and later bishop of Cracow, Lismanini, the Franciscan confessor of the queen, and others. In 1554 he published in Basel in the establishment of John Oporin his De republica emendanda, the fourth part of which consisted of his intended work, De Ecclesia, in which he dealt with the problem of church reform. Modrzewski was primarily a humanist, secondarily an advocate of religious reform. He strongly favored the establishment of a national church, independent of papal jurisdiction,[184] and leaned toward Calvinism.[185] In the first half of the sixteenth century humanism reached the height of its development and influence in Poland, and as a result brought about a radical mental and spiritual change. It freed the individual from the mediaeval burden of religious and intellectual authority; and while it did in turn impose new authorities, yet it awakened a sense of criticism, of intellectual and spiritual inquiry, and of independent judgment.[186] This new critical attitude of mind constituted a well prepared soil for the reception, growth, and development of the new seed of religious reform. This accounts in a large measure for the easy and rapid spread of the Reformation in Poland. In their search for truth the humanists disregarded the authority of the church, and subjected the established faith and ecclesiastical order to criticism. Criticism led, in turn, to rebellion against the dogmas of the church and its organization.[187]