When we here the word "Catholic" a lot of us (even lifelong Catholics) think of the things that make us uniqe - the Sacraments, Mass, Mary, purgatory, the Pope, etc. There is certainly nothing wrong with thinking about those things and our unique status and identity as a Church. But, this thinking is also very limited and if it stops there, it shows an improper understanding of the nature of the Church.
The biggest problem is in the way "Catholic Christian" is used, it insinuates Catholics are merely a subset of all Christians and therefore the larger group (represented by the word "Christian") has as a mere subset of it Catholics. We are merely a portion of this one "Christian" Church. Yet, this isn't what the Catholic Church teaches about itself.
Before I go any further, let me be clear. I am not saying that non-Catholic Christians are not united to the Church of Christ. Nor am I saying anything about their salvation (for more on these topics see the links at the bottom). Rather, I am making a positive affirmation of what the Catholic Church truly is and critiquing the use of the term "Catholic Christian", because it is not only insufficient as a descriptor of who we are as The Church of Christ, but it is also inaccurate and redundant.
If we are to understand the Catholic Church properly, we must understand her nature. This is what Vatican II says about the Church (emphasis added):
"This is the one Church of Christ which in the Creed is professed as one, holy, catholic and apostolic, which our Saviour, after His Resurrection, commissioned Peter to shepherd, and him and the other apostles to extend and direct with authority, which He erected for all ages as "the pillar and mainstay of the truth". This Church constituted and organized in the world as a society, subsists in the Catholic Church, which is governed by the successor of Peter and by the Bishops in communion with him, although many elements of sanctification and of truth are found outside of its visible structure. These elements, as gifts belonging to the Church of Christ, are forces impelling toward catholic unity." - LG 8The Church of Christ subsists in the Catholic Church, not the other way around. If the Catholic Church subsisted in the Church of Christ, then the term "Catholic Christian" would make more sense. But, as it is we should not use the term if we mean to reflect a true doctrine an orthodox understanding of our identity as Catholics.
To put it another way - there is one Church which Christ founded. That Church is the Catholic Church.
Another thought - "Catholic Christian" is redundant. Catholics are by definition Christians. As another document in Vatican II stated:
"it is only through Christ's Catholic Church, which is "the all-embracing means of salvation," that they can benefit fully from the means of salvation. We believe that Our Lord entrusted all the blessings of the New Covenant to the apostolic college alone, of which Peter is the head, in order to establish the one Body of Christ on earth to which all should be fully incorporated who belong in any way to the people of God." -UR 3Being Catholic is the very definition of being a Christian.
Just "Catholic" please.
**"Outside the Church There Is No Salvation"
**Is Receiving the Eucharist a Requirement for Salvation?
**Can Non-Catholics Be Saved?
**How Do We Know The Church Teaches Truth?