While the bishops were vainly prosecuting and persecuting the heretics, the Protestants were steadily strengthening their ranks by perfecting their organization and by effecting a very important union of the Calvinists with the Bohemian Brethren of Great Poland. During his temporary retreat in Great Poland in 1551, caused by Bishop Zebrzydowski’s persecution, Felix Krzyżak, superintendent of the Calvinistic churches of Little Poland, became acquainted with the Bohemian Brethren there, and invited them to unite with the Calvinists of Little Poland. After two preliminary conferences between the representatives of both groups, one held in Little Poland at Chrzęcice, in the possessions of Filipowski, and another in Great Poland at Gołuchow, in the possessions of Raphael Leszczyński, a Protestant synod was called together to meet at Koźminek, near Kalisz, in August, 1555, at which time a union between the two above mentioned bodies was effected. The basis of agreement was that each body retain its separate organization and its form of worship, while both were to work toward gradual uniformity in both respects.[141] The growth of Protestanism and the development of opposition had made the religious question exceedingly acute, and placed it at the Diet of 1555 in the very forefront of problems calling for immediate settlement. The importance of this question was fully recognized by the king himself, who had placed it among the matters to be discussed. Encouraged by the gains made at the Diet of 1552 and provoked by the high-handed repressive measures employed by the bishops, the Protestants planned to make a still more determined stand at this Diet against ecclesiastical Jurisdiction. At the provincial diets they chose, therefore, some of the most powerful magnates and most ardent Protestants, like Leszczyński, Ostrorog, and Marszewski of Great Poland, and Ossoliński, Siennicki, and others of Little Poland, as deputies of the Chamber.[142] The bishops, realizing the seriousness of the impending conflict, came out in force, and were ready to make concessions, if need be.[143] The Diet, called for the 22nd of April, 1555, met in first session on the 28th. As could have been expected, the Chamber again chose a Protestant for its president in the person of Nicholas Siennicki. In his speech of welcome to the king on behalf of the Chamber the next day, Siennicki stated the wishes of the szlachta. In brief, they wanted the abolition of ecclesiastical jurisdiction and full religious liberty. A project of adjustment was, therefore, worked out, having the full approval of the king and the secular members of the Senate, providing: (1) that everyone be at liberty to keep at home or at his church such clergymen as preached the pure Word of God; (2) that these be free to follow their own ritual and ceremonies; (3) that those wishing it be allowed to have the communion administered in both kinds; (4) that priests deprived of their benefices have them