The 4 marks of the church
From the Gospel of Matthew 16:18-19, we can see that Christ established a Church and gave to that Church authority. As Christianity spread and divergent sects began to spring up, it became vital to early Christians to be able to recognize the true Church and it’s teachings as it was handed down by the Apostles. Allusions to the Four Marks of the Church (especially Apostolic Succession) can be found in the writings of 2nd-century Church Fathers such as Ignatius of Antioch and Irenaeus of Lyons. While many doctrines, based on both tradition and different interpretations of the Bible, distinguish one denomination from another, the Four Marks were indications of which Church -and thus which doctrines- were of Apostolic origin.
the church is one
The Church, as Christ’s mystical body on earth, is united as one body of believers (Jn 17:20–23, 1 Cor. 12:-12-13, Phil. 2:2, Eph. 4:5-6). In the Catholic Church, this unity is made manifest through participation in the Eucharist and made visible through our recognition of Papal authority (Matt 16:18-19, Jn 21:15-17). Without the Eucharist, we are Christ’s Body in name only. Without an authority to rule definitively on a matter, any disagreement among members could ultimately lead to dissolution of our unity (Matt. 12:25, 1 Tim 3:15, Matt 18:17)
the church is holy
This phrase is not intended to convey a perpetual righteousness in the actions or behaviors of the individual members of the Church, as the Church is considered to be a refuge for sinners. Rather the word holy means set apart for a special purpose by and for God (John 15:19), just as the Tabernacle and Temple of the Old Covenant were visibly set apart. Catholics understand the holiness of the universal Church is derived from Christ’s holiness (Eph. 5:25-27) as the Church is the mystical Body of Christ (1 Cor. 12:12-13). The Church then provides its members the means of holiness through the Sacraments it offers.
the church is catholic
The word “catholic” is derived from the Greek adjective καθολικός (katholikos), meaning “universal”. Although the church is spread throughout the world (Matt. 28:19–20, Rev. 5:9–10, Gal. 3:28), each local manifestation of the church contains the wholeness of the Christian faith, full and complete, all-embracing, and with nothing lacking. Although cultural practices, garments, rites, etc may differ from place to place, the essential doctrines and dogmas expressed in each place are universal.
the church is apostolic
The Church’s foundation and beliefs are rooted in the living Tradition of the Apostles (Eph. 2:19–20, 2 Tim. 2:2, 2 Thess. 2:15, 1 Cor. 11:2) and continue through the apostolic succession of bishops who derive their authority through a direct line of laying on of hands from the apostles (Acts 6:6, Acts 13:3, 1 Tim 4:14, 2 Tim. 1:6). This Apostolic Succession is made apparent by tracing the lineage of bishops of the various churches back to their original founding Apostles or close acquaintances of the Apostles. This line of succession was very important to the Christians of the first three centuries as this was the litmus test for verifying true doctrine and Apostolic Tradition