The problems of contemporary Catholic authority are compounded by the fact there are some nine categories of Roman Catholicism around the world. The distinctions between them are often not clear because they may tend to overlap and merge or blur into one another. Nor would individual Catholics necessarily appreciate or agree with such labels. But they will serve as a convenient grouping for purposes of illustration:

If we consider several of these categories in a bit more detail, we will be better able to understand modern Catholicism. First, it should be noted that for Rome, once a person is baptized a Catholic, they are officially held to remain a Catholic, regardless of their degree of variation from Rome. Thus, even the nominal, pagan and evangelical "Catholics" (point 10 above) may be deemed genuinely Catholic irrespective of spiritual condition or belief. This is so because of what Catholics maintain happens in baptism and through other Church sacraments: in essence, with few exceptions once baptized a Catholic, always a Catholic.

Nominal, modernist, and cultural Roman Catholics comprise millions of persons and possibly the majority of American Catholics. In large measure they are born Catholic and have become emotionally attached to the "Mother Church." Characteristically, however, they do not understand or reject its authority and are not too concerned with obedience to the ethics or practices of the Church. Like many liberal Protestants, they remain Catholics primarily because of social convenience, religious needs, or perhaps, personal guilt rather than conviction concerning Rome’s authority.

Syncretistic/eclectic Catholics are possibly more representatively described as "pagan" Catholics because, while accepting the Catholic faith to some degree, they have also retained much or most of their indigenous pagan religion. As a result, Catholic beliefs and practices are combined with animistic beliefs and practices so that a blending of the two occurs.

The traditionalists are arguably the most influential segment of the Church because through the Pope, bishops and orthodox priests, they occupy the center of power in Catholicism. Traditionalists believe that by being obedient to the Church they are, in essence, being obedient to God and Christ. Why? Because they have been taught that whatever the Church decrees as orthodox belief and practice through its tradition is, by definition, the will of God. 2 Thus, to obey the Church is equivalent to submitting to what God has revealed as His will for a person’s life. As a result, the traditional Catholic feels no need to examine the Bible for himself to determine whether or not what the Church teaches is actually biblical. Why? He has been taught that the Church has been granted divine power to interpret the Bible infallibly. As a result, he completely trusts whatever the Church tells him that the Bible teaches.

The liberal branch of the Church is "liberal" largely in relationship to the authority of Rome and not necessarily liberal in the Protestant sense of being primarily rationalistic. Liberal Catholics vary widely in the degree to which they have departed from traditional Catholicism. One example would be Catholic theologians who may question the legitimacy of papal infallibility, or the Church’s teaching on justification, or birth control—but who otherwise seek to remain loyal to Rome. Another example would be the Marxist oriented "liberation theology" of many Central and South American priests and theologians whose primary concern is more "political liberation" and "social justice" than anything principally biblical or spiritual.

Nevertheless, although the term "liberal" is used specifically in relationship to the authority of Rome, there are also many Catholic leaders who are more or less liberal in a Protestant sense in that they reject biblical authority, deny Christ’s deity, teach universalism, etc.

Charismatic Catholics emphasize faith as a personal commitment to Jesus and loyalty to Scripture. This branch of Catholicism frequently encourages Bible studies, speaking in tongues, and oftentimes a "born again or Baptism in the Spirit" experience. But more frequently than not, it remains Roman Catholic, attempting to integrate this newfound faith and experience with traditional doctrines involving Mary, papal authority, and the sacraments. In fact, in practice the Catholic experience of the "baptism in the Holy Spirit" actually seems to lead most often to greater devotion to Catholic beliefs and practice. For example, thousands of Catholics have reported how the "baptism in the Spirit" affected them in terms like the following: "the mother of God has become more special"; "I have a deeper devotion to Mary," and "I have taken up the Rosary since baptism in the Spirit." 3

The Evangelical "Catholic" is truly an Evangelical believer and not a Catholic. In other words, he is not a committed Roman Catholic who merely appropriates the title of Evangelical Christian. He understands the issues doctrinally and spiritually and attempts to walk what can be a very difficult, and to some people’s minds, inconsistent, line of fidelity to the Bible while remaining a member of the Roman Catholic Church. That this can, occasionally, be successfully negotiated is known personally to co-author Weldon. A friend of his in Bible School had such a love for Catholics that he not only found a parish which accepted his Evangelical training as priestly ordination but whose superiors permitted him to teach the Bible in its entirety on the basis of personal conscience—i.e., as an Evangelical Protestant. Not that it was easy: his parish got so much Bible that many of them decided that they were no longer Catholics while others attempted a synthesis of Evangelical Catholicism. Nevertheless, how the situation finally ended, we were unable to determine.