2.4. Can Catholic doctrine or dogma change over time?

Absolutely not. Dogma is a truth revealed by God and solemnly defined by the Church. Doctrine is any teaching on faith or morals proposed as part of the deposit of faith. When defined or universally taught by the Church’s Magisterium, both are infallible and irreformable.

“The meaning of sacred dogmas is ever to be maintained which Holy Mother Church has once declared, and there must never be any deviation from that meaning.”

— First Vatican Council, Dei Filius, 1870

The pope has no power to invent new dogmas, contradict prior dogmas, or reinterpret doctrine in a way that opposes what the Church has always taught.