While sharing the denomination of "Catholicism", Second Reformation Catholicism was distinct from at least one Catholic faith practiced on Old Earth.
Second Reformation Catholicism was a Christian faith, and shared many tenets of belief with other Christian denominations such as the Grayson branch of the Church of Humanity Unchained. The Church recognized apostolic succession from the beginning of Christianity.
Throughout the millennia, the Catholic Church has been forced to reevaluate and reassess many elements of their beliefs, and by the 20th Century PD, it accepted the ordination of women into the priesthood and the marriage of priests, along with polygamy. The Church practiced baptism and marriage among its sacraments. It also included the Ten Commandments as principles of faith, and its prayers included the Apostles' Creed and the Lord's Prayer.
In 1920 PD, both the Reverend of the Church of Humanity Unchained, Jeremiah Sullivan, and the Catholic Archbishop of Manticore, Robert Telmachi, declared that they found no irreconciliable elements between their respective religious faiths. (HH11)
Second Reformation Catholicism had an ordained priesthood which included both men and women, and its members were allowed to marry. The Church was organized around districts known as dioceses, and the planet Manticore fell under the Archdiocese of Manticore, whose head in the 1910s and 1920s PD was Archbishop Robert Telmachi. Also, the Church maintained diplomatic representations to star nations. In 1920 PD, the Catholic representative to Grayson was Monsignor Davidson.
Members of the Church referred to it as "Mother Church", in contrast to the Graysons' use of "Father Church" to refer to the Church of Humanity Unchained. (HH11)
Despite the mandated separation between church and state and the explicit prohibition of an official state religion enshrined in the Manticoran constitution, the members of the House of Winton had been practicing Second Reformation Catholics for at least four centuries prior to 1911 PD, and contributed to the faith in the Star Kingdom of Manticore, with King Michael providing funds from the Royal Family's private fortune to build King Michael's Cathedral in Landing. (HH8)