Catholicism is a denomination, hence a subset, of Christianity. All Catholics are Christians, but not all Christians are Catholics. A Christian refers to a follower of Jesus Christ who may be a Catholic, Protestant, Gnostic, Mormon, Evangelical, Anglican or Orthodox, or follower of another branch of the religion.
A Catholic refers to a Christian who follows the Catholic religion as transmitted through the succession of Popes of Rome and the Vatican Empire across history. The Pope is the leader of the Catholic church. The Catholic Church is the largest of the Christian Churches - about 60% of Christians are Catholic.
While Catholicism preaches and believes the Roman catholic church to be the supreme authority, Christianity encompasses all churches as well as individuals without churches, as many modern practitioners may be believers in Christ but not active church goers. Both Catholics and other kinds of Christians will study the Bible, attend church, seek ways to introduce the teachings of Jesus into his or her life, and engage in prayer.
Catholics also follow the teachings of Jesus Christ but do so through the church, whom they consider as the path to Jesus. They believe in the special authority of the Pope which other Christians may not believe in, whereas Christians are free to accept or reject individual teachings and interpretations of the bible. Catholics and Christians seek forgiveness for their personal sins through faith in Jesus Christ. The goal of the Christian and Catholic is the manifestation of the Kingdom of God on Earth and the attainment of Heaven in after-life.
The Catholic Church teaches the doctrines of Jesus Christ as transmitted in the New Testament of the Bible, as well as the teachings, Psalms, and histories of the Jewish prophets in the Old Testament. The Catholic Religion preserves a tradition of Priesthood, Monks, and Nuns that date back to the early middle ages and before. The Catholic Religion is based on the entire Bible, especially in the direct teachings of Jesus given in the New Testament of the Bible. Other non-Catholic Christian texts based on the teachings of Jesus include the Gnostic Gospels.
Christians and Catholics believe salvation is a gift by means of the unmerited grace of God, a gift from a loving heavenly Father who sent His only begotten Son Jesus to be their savior. They believe that, through faith in Jesus, one can be saved from sin and eternal death. However, the Bible records in John 3:3-10 that in order for anyone to enter the Kingdom of Heaven, one must be born again by the Spirit of God. This was taught by the Lord Jesus Christ Himself and is recorded in scripture in both Catholic and Protestant Bibles. Catholics do believe that one becomes born again at Baptism. Christians believe that once you believe and have faith in Christ you are born again. You don't have to be baptized to be a Christian, but in all the scriptures, people receive Christ, then they are baptized. Baptism is the representation of dying with Christ and being raised with him.
The teachings of the Catholic Church are derived from two sources, firstly the Sacred Scriptures (the Bible) and secondly the Sacred Tradition. Catholicism, like Christianity regards the Holy Bible, a collection of canonical books in two parts (the Old Testament and the New Testament) as authoritative: written by human authors under the inspiration of the Holy Spirit, and therefore the inerrant word of God. So in a way both follow the Bible as their central scripture, however there are nine books that are left out from modern Christian translations.
Video explaining the differences
The following video explains the doctrinal differences between Roman Catholics, Eastern Rite Catholics, and Orthodox Christians.
The first known usage of the term Christians can be found in the New Testament of the Bible. The term was thus first used to denote those known or perceived to be disciples of Jesus. Similarly, in the two other New Testament it refers to the public identity of those who follow Jesus.
The history of early Christianity, including Catholicism is told in Acts in the New Testament. The early days of Christianity witnessed the desert Fathers in Egypt, sects of hermits and Gnostic ascetics. Christianity began in 1st century AD Jerusalem as a Jewish sect but spread throughout the Roman Empire and beyond to countries such as Ethiopia, Armenia, Georgia, Assyria, Iran, India, and China.
Roman Catholicism traces its history to the apostles, especially the Apostle Peter. St. Peter is considered the first pope, and every Pope since is regarded as his spiritual successor. It was only after the first thousand years of Christianity that this new denomination of Catholicism came into being. This was for those people who wanted to follow God through the Church. They give the leader of the church spiritual authority to provide a means for resolving disputes that could divide the church. Roman Catholicism was not initiated until the First Ecumenical Council in A.D. 325. At this point, corrupt church leaders were attempting to take power in the Byzantine Roman Empire. The first unified Roman Catholic Church was created in A.D. 606 with world-wide leadership. It is virtually impossible to trace the origin of the Papacy, as the early Christians maintained their records in the Catacombs in Rome. The Church of Rome took control of the catacombs and revised the documents to include the title Pope for any early church leader that was deemed worthy. Roman Catholic Tradition and the Catechism of the Catholic Church prevail over scripture in every context. Scripture is used as a reference. During their rise to political power in A.D. 300-500, the Church or Rome accepted Pagan and Roman society as holy and acceptable to appease the population. During this time, the Church of Rome (not yet universal) declared anyone who disagreed with their teachings as a heretic. Heretics were killed by the Church of Rome for any belief outside of Christianity and their written works were destroyed. During the plagues circa A.D. 500, many people abandoned the cities and the sick. After this dark period, the full Catholic Church entered into society.
The Pope View
The idea of the "pope" actually existing from the beginning of the church is scripturally correct as Christ had declared Peter, the spiritual rock. It was the Holy Spirit who instituted the church when He visited the 120 people in the Upper room on the day of Pentecost. Acts 2. On that day the "Christian Church was born when 120 were "filled" with the Holy Spirit and tongues of fire rested upon their heads. They then began to "speak in tongues" as evidence of being filled with the Holy Spirit.
View of Homosexuality
Throughout the majority of Christian history most theologians and Christian denominations have viewed homosexual behavior as immoral or sinful. However, in the past century some prominent theologians and Christian religious groups have espoused a wide variety of beliefs and practices towards homosexuals, including the establishment of some 'open and accepting' congregations. In Roman Catholicism, homosexual acts are contrary to natural law and sinful while homosexual desires are disordered (but not necessarily sinful). Both the Catholic church and other Christian denominations have had priests or pastors who were gay. All homosexual priests have been censured by the Catholic Church.
The Catholic Religion has a historical lineage and hierarchy that is centered in the Pope and Vatican City in Rome. The Catholic Religion was the source of the Protestant and Anglican Churches as they evolved to break with Papal authority. Catholics do not allow priesthood to women.
A Christian may follow any church based in the New Testament. Some churches permit female priests, while others do not. Both Catholics and Christians venerate the Mother of Jesus, Mary, as well as the 12 disciples as the principal teachers of the faith. The Pope is not regarded as the supreme authority by Christianity. Some denominations of Christianity allow women to become priests after ordination.
Worships and Practices
Roman Catholics and Christians believe that all people should strive to follow Christ's commands and example in their everyday actions. For many, this includes obedience to the Ten Commandments. Christian practices include acts of piety such as prayer and Bible reading which even Catholics follow. Christians and Roman Catholics assemble for communal worship on Sunday, the day of the resurrection, though with Christians other liturgical practices often occur outside this setting. At Mass the Scripture readings are drawn from the Old and New Testaments.
In the Catholic Church, there is a distinction between Liturgy, which is the formal public and communal worship of the Church, and personal prayer or devotion, which may be public or private. Other Christians may not have such a system and may all pray together. The Liturgy is regulated by church authority and consists of the Eucharist (the Mass), the other Sacraments, and the Liturgy of the Hours. All Catholics are expected to participate in the liturgical life.