There was little difficulty in arranging that the Protestant princes, who, before the date of the Convention of Passau, had seized ecclesiastical property within their own territories, either for their own purposes or for the support of Protestant worship, should no longer be subject to the law or authority of the Catholic clergy. The real difficulty arose in providing for the future. With Protestantism as a growing religion, the princes might be inclined to proceed further with the secularizing of the Church property still left untouched within their own territories; and besides this, it was possible that even bishops or abbots themselves, being princes of the Empire, might be inclined to abandon their religion, and to adopt Protestantism. [Sidenote: § 7. Might the princes seize more lands?] The first of these difficulties was left by the treaty in some obscurity; but, from the stress laid on the abandonment by the Catholics of the lands secularized before the Convention of Passau, it would seem that they might fairly urge that they had never abandoned their claims to lands which at that date had not been secularized. [Sidenote: § 8. Might the ecclesiastics turn Protestants?] The second difficulty led to long discussions. The Protestants wished that any bishop or abbot who pleased might be allowed to turn Protestant, and might then establish Protestantism as the religion of his subjects. The Catholics insisted that any bishop or abbot who changed his religion should be compelled to vacate his post, and this view of the case prevailed, under the name of the Ecclesiastical Reservation. It was further agreed that the peace should apply to the Lutheran Church alone, no other confession having been as yet adopted by any of the princes. [Sidenote: § 9. Dangers of the future.] Such a peace, acceptable as it was at the time, was pregnant with future evil. Owing its origin to a Diet in which everything was arranged by the princes and electors, it settled all questions as if nobody but princes and electors had any interest in the matter. And, besides this, there was a most unstatesmanlike want of provision for future change. The year 1552 was to give the line by which the religious institutions of Germany were to be measured for all time. There was nothing elastic about such legislation. It did not, on the one hand, adopt the religion of the vast majority as the established religion of the Empire. It did not, on the other hand, adopt the principle of religious liberty. In thinking of themselves and their rights, the princes had forgotten the German people. [Sidenote: § 10. Fresh encroachments upon Church lands.]