of his immediate predecessors: Pope Pius XII and Pope John XXIII. Universal call to holiness According to Pope Paul VI, "the most characteristic and ultimate purpose of the teachings of the Council" is the universal call to holiness: "all the faithful of Christ of whatever rank or status, are called to the fullness of the Christian life and to the perfection of charity; by this holiness as such a more human manner of living is promoted in this earthly society." This teaching is found in Lumen Gentium, the Dogmatic Constitution on the Church, promulgated by Paul VI on 21 November 1964. Church reforms Synod of Bishops On 14 September 1965, he established the Synod of Bishops as a permanent institution of the Catholic Church and an advisory body to the papacy. Several meetings were held on specific issues during his pontificate, such as the Synod of Bishops on evangelisation in the modern world, which started 9 September 1974. Curia reform Pope Paul VI knew the Roman Curia well, having worked there for a generation from 1922 to 1954. He implemented his reforms in stages. On 1 March 1968, he issued a regulation, a process that had been initiated by Pius XII and continued by John XXIII. On 28 March, with Pontificalis Domus, and in several additional Apostolic Constitutions in the following years, he revamped the entire Curia, which included reduction of bureaucracy, streamlining of existing congregations and a broader representation of non-Italians in the curial positions. Age limits and restrictions On 6 August 1966, Paul VI asked all bishops to submit their resignations to the pontiff by their 75th birthday. They were not required to do so but "earnestly requested of their own free will to tender their resignation from office". He extended this requirement to all cardinals in Ingravescentem aetatem on 21 November 1970, with the further provision that cardinals would relinquish their offices in the Roman Curia upon reaching their 80th birthday. These retirement rules enabled the Pope to fill several positions with younger prelates and reduce the Italian domination of the Roman Curia. His 1970 measures also revolutionised papal elections by restricting the right to vote in papal conclaves to cardinals who had not yet reached their 80th birthday, a class known since then as "cardinal electors". This reduced the power of the Italians and the Curia in the next conclave. Some senior cardinals objected to losing