Want to start a fight? Just ask this question: How many Protestant denominations are there in the world?

Estimates start as high as 40,000 and most sources put the number above 20,000, citing the United Nations, the World Christian Encyclopedia or some other authority. The key is that various Protestant groups have their own concepts of biblical authority and the role played by the conscience of each believer. Fights often cause splits and new flocks.

Meanwhile, the Church of Rome has the Throne of St. Peter and the Catechism. This is why eyebrows were raised when progressive theologian Daniel Maguire of Marquette, amid tense debates about marriage, divorce and gay rights, wrote to The New York Times to argue that Catholicism is "going the way of its parent, Judaism" and dividing into three streams.

"In Judaism there are Reform as well as Conservative and Orthodox communities. This arrangement is not yet formalized in Catholicism, but the outlines of a similar broadening are in place," said Maguire. While the Vatican may tweak some procedures, such as streamlining the annulment process, "reform Catholics don't need it. Theirconsciences are their Vatican."

The tricky word "conscience" crept into news about the 2015 Synod of Bishops in Rome -- focusing on marriage and family life -- when the leader of the giant Archdiocese of Chicago told reporters that he thought many Catholics who under current teachings cannot take Holy Communion should be able to do so, if guided by their consciences.

"In Chicago I visit regularly with people who feel marginalized, whether they're elderly or the divorced and remarried, gay and lesbian individuals, also couples," said Archbishop Blase Cupich, who was personally invited to the synod by Pope Francis. His remarks were recorded and featured in secular and religious publications.

"I try to help people along the way. And people come to a decision in good conscience," said Cupich. "Then our job with the church is to help them move forward and respect that. The conscience is inviolable."

Asked by a reporter from the conservative LifeSiteNews if this approach includes gay couples, he said, "gay people are human beings too and they have a conscience. And my role as a pastor is to help them to discern what the will of God is by looking at the objective moral teaching of the church and yet, at the same time, helping them through a period of discernment to understand what God is calling them to at that point."

Others sharply disagreed with this kind of approach -- especially leaders of the growing churches of Africa, Asia and the Global South. In a speech text released to the public, Cardinal Robert Sarah of Guinea -- who leads the Vatican's Congregation for Divine Worship and the Discipline of the Sacraments -- warned that Catholics are wrestling with two "apocalyptic beasts." One, he said, is the "idolatry of Western Freedom" and the other is "Islamic fundamentalism."

"To use a slogan, we find ourselves between 'gender ideology and ISIS,' " he said. The subtle threat is the "temptation to yield to the mentality of the secularized world and the individualistic West. ... The Gospel that once transformed cultures is now in danger of being transformed by them." Some of the 2015 synod proceedings, he added, seemed to "promote a way of seeing typical of certain fringe groups of the wealthiest churches. This is contrary to a poor church, a joyously evangelical and prophetic sign of contradiction to worldliness."

Catholics, he said, must dare to "proclaim the truth without fear, i.e. the plan of God, which is monogamy in conjugal love open to life."

Nevertheless, argued Archbishop Mark Coleridge of Brisbane, Australia, conservative Catholics who are currently hurling "lemon-lipped diatribes this way and that" need to realize that it's acceptable to change a few details "not so much of what the church teaches but of what her pastoral practice has been." Synod debates will not cause the "whole edifice built up over 2000 years" to "come tumbling down," he added, writing online.

Change is coming, despite Catholic "voices of fear" and "even panic," he stressed. It's clear that "those voices, clinging desperately to some imagined or ideologised past, cannot point the way into the future. History will have its way, however much we try to cling to illusions of timelessness."