Nonsense. Whatever you have to say about the roots of other denominations makes no difference to the truth that Christianity is a religion, and all who follow it are Christians. Those who organize themselves into different groups to practice it are organised into what are called denominations. Notwithstanding people of some denominations who think God has a pecking order for belivers.
Jesus wasn't a Christian, he was a Jew. He sure wasn't Catholic or a Presbyterian or a Baptist.
Those who organize themselves into different groups to practice it are organised into what are called denominations.Peter and the Twelve did not self-organize the basic structure of the Church. Christ Jesus did.
To denominate is to select a name to differentiate yourself from the existing. The Catholic Church has always existed. Other sects have broken away from the Mother Church, having to denominate themselves for distinction.
If there is one river it needs no name. Only when a branch shoots off is there a need to name the offshoot. The original river is still nameless.
SD
"Religion" can be used in the sense of Catholic vs. Baptist (usually referred to as "war" (j/k)) or as Christian vs. Jewish.
Religion: A personal or institutionalized system grounded in such belief and worship (dictionary.com)
Denomination could be used to describe Catholicism as a Christian church, but it is typically used in the sense of: Catholics vs. various Protestant denominations, and as such has the connotation of Protestantism. I'm not even sure evangelicals, who do not consider themselves Protestants, would refer to their 'denomination', but that may be because many don't have a denomination or are not wide-spread enough to be considered as "A large group of religious congregations". Whatever the reason, the term is typically applied to mainline Protestant churches.
The Catholic Church has been using the same Creed for over a thousand years; it's pretty silly to claim that the Protestant denominations have an equal claim on Church history, since at the time they split off from the standard structure and belief all Christians had been professing the same faith for several hundred years that later became known as Catholic, even if you dismiss the belief in Peter's role as the first Pope.