Is Roman Catholic Dogma really used, by necessity, in Scriptural interpretation?

Question

The following is taken from the body of a recently asked question asking how many in the New Testament are called or actually claim to be the brother or sister of Jesus Christ. It is not scoped for Catholic answers only but it is asked by a Catholic and from a Catholic perspective:

Regardless of the doctrine of the Perpetual Virginity of Mary acknowledged as dogma by most Christians, which would necessitate a different interpretation of the words "brother" and "sister"

It appears by this statement as though Roman Catholics, by necessity, assign interpretations to words in Scripture based upon Dogmatic statements made from Rome rather than their plain biblical usage. The Perpetual Virginity of Mary was dogmatized in 553 in Constantinople but it had been talked about within the church since it's possible earliest witness in the apocryphal Protogospel of James (circa 150). The Assumption of Mary, however, wasn't dogmatized until 1950 and, arguably has no biblical attestation.

I don't know if there are any specific words in Scripture whose meanings, by necessity, must be interpreted differently due to accepting the dogma of Mary's Assumption but theoretically it is possible. Do Roman Catholics, by necessity, assign meanings to words in the Bible based upon dogmatic statements made hundreds and even thousands of years after the Apostles were finished writing Scripture? Is this really how Roman Catholics interpret Scripture?

Answer 1

Given that a dogma is something that is known to be true, how can it not be involved with the interpretation of Scripture?

For instance, I personally believe in the laws of physics and in particular the one about gravity, so when I read:

And he brought him to Jerusalem, and set him on a pinnacle of the temple, and said unto him, If thou be the Son of God, cast thyself down from hence:
— Luke 4:9

my belief in gravity forces me to interpret this as a suggestion to commit an almost certainly fatal act, and not as a suggestion to fly around like Superman.

When Satan continues:

For it is written, He shall give his angels charge over thee, to keep thee: And in their hands they shall bear thee up, …

I can see it only as confirming that interpretation.

It would not occur to me to think that my interpretation is wrong. But if I considered that it might be wrong, and even if I eventually concluded that it was wrong, it still wouldn't affect my belief in gravity; it was only my application of gravity to this situation that was wrong.

In the case of Jesus having siblings from his mother though, a belief in her perpetual virginity would not only make one conclude that any references to siblings must be figurative, any doubt about this interpretation would also cast doubt on the perpetual doctrine. And since that is known to be true, the doubt can be removed from the interpretation too.
(If "A is false" implies that "B is false", and B is known to be true, then A must be true.)

Everything we learn or conclude must be based on what we already know to be true.

Answer 2

Catholics do not "assign interpretations" to Scripture. It is the Church's prerogative to explain Sacred Scripture and guard the deposit of faith.

Pope Pius X, Lamentabile, The Errors of the Modernists, July 3, 1907, #22: “The dogmas which the Church professes as revealed are not truths fallen from heaven, but they are a kind of interpretation of religious facts, which the human mind by a laborious effort prepared for itself.” - Condemned

Since dogmas are truths fallen from Heaven, any true interpretation must be in accord with them.

What I assume you mean to imply by your question is that the Church somehow claims authority over the word of God, which is not true.

St. Robert Bellarmine, On The Church: On Councils, Ch. XII "Whether the authority of a Council is greater than Scripture"

(...) The heretics of this time everywhere cry out that we subject Scripture to Councils. (...) Moreover, this is not our blasphemy, but is their strawman. For Catholics do not subject the Sacred Scripture to Councils, but places it before them; nor is there any controversy on this point. But if some Catholics sometimes say scripture depends on the Church, or a Council, they do not understand this in regard to its authority, or according to what it is, but in regard to the explanation and regard to us. (...) But Councils do not have, nor write immediate revelations, or the words of God, rather they only declare what indeed the word of God is, written or handed down, and how it ought to be understood; besides, they deduce conclusions from it by reasoning. Consequently, when Councils define what are the canonical and divine books, they do not cause them to be of infallible truth, but only declare that they are such.