Making Faith Our Own

Doctrine of the Sacred Scripture 59 describes how doctrine that we grew up with can become our own.

Those however who do not procure doctrine for themselves, first make investigation as to whether the doctrine delivered by others and received by the general body accords with the Word, and they assent to what accords, and from what does not accord they dissent. In this way it becomes to them their own doctrine, and through doctrine their faith. But this takes place only with those who not being taken up with worldly affairs are able to exercise discernment. If these persons love truths because they are truths, and make them of use for life, they are in enlightenment from the Lord.

Apocalypse Explained 190 takes it a step further, saying that people who do this right don't just compare what they've heard from other people with the Word, they look at the Word "as if they were separated from that doctrine."

[W]hen [those who are in the spiritual affection of truth] read the Word they do not look at it from the doctrine of the church in which they are born, but they look at it as if they were separated from that doctrine; for their wish is to be enlightened, and to see truths inwardly in themselves, and not from others.