But these were no longer necessary.

They had done their duty in bringing the Council to a favorable close, and in establishing the Catholic concordat.

What was now required was a Pope who should, by personal example and rigid discipline, impress Rome with the principles of orthodoxy and reform.
Carlo Borromeo, self-conscious, perhaps, of the political incapacity which others noticed in him, and fervently zealous for the Catholic Revival, devolved this duty on Michele Ghislieri, who completed the work of his two predecessors.
Paul IV.

had laid a basis for the modern Roman Church by strengthening the Inquisition and setting internal reforms on foot.

Pius IV., externally, by his settlement of the Tridentine Council, and by the establishment of the Catholic concordat, built upon this basis an edifice which was not as yet massive.