Why do Catholics give equal importance to what has been handed down
in Tradition with what has been revealed in the Bible?

The Bible is a veritable library of different genre of books: eye witness accounts, beautiful stories attempting to explain difficult truths, parables, allegories and poetry. It sometimes cannot be taken literally (no one cuts off his/her hand as Jesus suggests); it must always be taken seriously (we must take up our cross to be Jesus' follower).

The Second Vatican Council, in a document called Verbum Dei (or "Word of God") taught: "Thus, by the light of the Spirit of truth, these successors can in their preaching preserve this word of God faithfully, explain it, and make it more widely known. Consequently it is not from sacred Scripture alone that the Church draws her certainty about everything which has been revealed. Therefore both sacred Tradition and sacred Scripture are to be accepted and venerated with the same devotion and reverence."

The teaching of the Church and the teachings in the Bible are not in opposition, but rather mutually complement one another and, consequently, grow our faith. Catholics trust that the Holy Spirit who worked in minds of those who wrote the books of the Bible is also at work in those who interpret them today.