The Church was able to establish the books that truly belonged in the Bible because of its tradition that some of the laws issued by the pope are infallible. Another tradition holds that the Church cannot have erred in its past rulings, though it can err in its actions. This is actually a modified definition of papal infallibility, devised by the 1965 Vatican II Council. (From the time of Vatican I, all popes were seen as infallible in both their teachings and their actions.)

Catholics are expected to accept the Church's interpretation of God's Word as inspired by the Holy Spirit. The Bible, being God's Truth, is seen as equally infallible.

Papal Infallibility

The pope, who is the visible head of the Church, is infallible in his teachings on matters of religion in morality. However, the Church does recognize the fact that popes can and do make mistakes in their actions. Teaching must now be “received” by the whole Church to be seen as truly infallible.

This evolving concept of infallibility has eased ecumenical discussions with other religions. Pope John Paul II, in his overtures to the Eastern Orthodox Church, acknowledged that the Church erred in its actions and contributed to the Great Schism that split the Catholic Church.

Scriptural Infallibility

Scripture is a Sacred Deposit entrusted to the care of the Church. The Catholic Church considers all of the Scriptures to be sacred and infallible; because they are God's Word dictated through the Holy Spirit, they are entirely true and correct. The Church acknowledges that the Bible sometimes contains contradictory verses and advice. However, Church fathers believe that each passage must be studied in the context in which it was originally written and in light of the overall message of God's love.