In the same year he was raised to the office of chancellor of Scotland, and was appointed protonotary apostolic and legate a latere by the pope.
At the age of twenty-five he held several rich livings, had been notary and protonotary to the Curia, and was first secretary to the pope, in which capacity he conducted the correspondence with the nuncios (among them Pier Paolo Bergerio in Germany) and a host of other duties.
Before this he had been sent by Archbishop Affre to Rome, and had been appointed Roman prelate and protonotary apostolic. For thirty years he remained a notable figure in France, doing his utmost to arouse his countrymen from religious indifference.
He was created a protonotary apostolic, and in July returned to Germany, as papal nuncio, with the celebrated bull Exsurge Domine directed against Luther's writings.