The issue concerning any church and its practices should be “Is this Biblical?” If a teaching is Biblical (taken in context), it should be embraced. If it is not, it should be rejected. God is more interested in whether a church is doing His will and obeying His Word than whether it can trace a line of succession back to Jesus’ apostles. Jesus was very concerned about abandoning the Word of God to follow the traditions of men (Mark 7:7). Traditions are not inherently invalid…there are some good and valuable traditions. Again, the issue must be whether a doctrine, practice, or tradition is Biblical. How then does the Roman Catholic Church compare with the teachings of the Word of God?
Salvation: The Roman Catholic Church teaches that salvation is by baptismal regeneration and is maintained through the Catholic sacraments unless a willful act of sin is committed that breaks the state of sanctifying grace. The Bible teaches that we are saved by grace which is received through simple faith (Ephesians 2:8-9), and that good works are the result of a change of the heart wrought in salvation (Ephesians 2:10; 2 Corinthians 5:17) and the fruit of that new life in Christ (John 15).
Assurance of salvation: The Roman Catholic Church teaches that salvation cannot be guaranteed or assured. 1 John 5:13 states that the letter of 1 John was written for the purpose of assuring believers of the CERTAINTY of their salvation.
Good Works: The Roman Catholic Church states that Christians are saved by meritorious works (beginning with baptism) and that salvation is maintained by good works (receiving the sacraments, confession of sin to a priest, etc.) The Bible states that Christians are saved by grace through faith, totally apart from works (Titus 3:5; Ephesians 2:8-9; Galatians 3:10-11; Romans 3:19-24).
Baptism: In the New Testament baptism is ALWAYS practiced AFTER saving faith in Christ. Baptism is not the means of salvation; it is faith in the Gospel that saves (1 Corinthians 1:14-18; Romans 10:13-17). The Roman Catholic Church teaches baptismal regeneration of infants, a practice never found in Scripture. The only possible hint of infant baptism in the Bible that the Roman Catholic Church can point to is that the whole household of the Philippian jailer was baptized in Acts 16:33. However, the context nowhere mentions infants. Acts 16:31 declares that salvation is by faith. Paul spoke to all of the household in verse 32, and the whole household believed (verse 34). This passage only supports the baptism of those who have already believed, not of infants.
Prayer: The Roman Catholic Church teaches Catholics to not only pray to God, but also to petition Mary and the saints for their prayers. Contrary to this, we are taught in Scripture to only pray to God (Matthew 6:9; Luke 18:1-7).
Priesthood: The Roman Catholic Church teaches that there is a distinction between the clergy and the “lay people,” whereas the New Testament teaches the priesthood of all believers (1 Peter 2:9).
Sacraments: The Roman Catholic Church teaches that a believer is infused with grace upon reception of the sacraments. Such teaching is nowhere found in Scripture.
Confession: The Roman Catholic Church teaches that unless a believer is hindered, the only way to receive the forgiveness of sins is by confessing them to a priest. Contrary to this, Scripture teaches that confession of sins is to be made to God (1 John 1:9).
Mary: The Roman Catholic Church teaches, among other things, that Mary is the Queen of Heaven, a perpetual virgin, and the co-redemptress who ascended into heaven. In Scripture, she is portrayed as an obedient, believing servant of God, who became the mother of Jesus. None of the other attributes mentioned by the Roman Catholic Church have any basis in the Bible. The idea of Mary being the co-redemptress and another mediator between God and man is not only extra-biblical (found only outside of Scripture), but is also unbiblical (contrary to Scripture). Acts 4:12 declares that Jesus is the only redeemer. 1 Timothy 2:5 proclaims that Jesus is the only mediator between God and men.
Many other examples could be given. These issues alone clearly identify the Catholic Church as being unbiblical. Every Christian denomination has traditions and practices that are not explicitly based on Scripture. That is why Scripture must be the standard of Christian faith and practice. The Word of God is always true and reliable. The same cannot be said of church tradition. Our guideline is to be: “What does Scripture say?” (Romans 4:3; Galatians 4:30; Acts 17:11). 2 Timothy 3:16-17 declares, “All Scripture is God-breathed and is useful for teaching, rebuking, correcting, and training in righteousness, so that the man of God may be thoroughly equipped for every good work.”
Recommended Resource: Reasoning from the Scriptures with Catholics by Ron Rhodes.