“When I was a child, I spoke like a child, I thought like a child, I reasoned like a child.
When I became a man, I gave up childish ways.”
1 Corinthians 13:11 (ESV)

As a general rule for discernment, we should not be in the habit of just “swallowing” whatever is fed to us. We need a discriminating taste for truth. Discerning truth is a practiced skill that we can cultivate by regular exposure to the truth, deep familiarity with the truth, and habitually searching for truth. That way, when a new idea or worldview is set before us in a sermon, in a movie, through a teacher’s lesson plans, or in a friend’s conversation, we are already well prepared to “process” that idea, distinguish the good, true, and beautiful parts and spit out the rest. This ability to “chew your food” is absolutely vital for spiritual maturity. We expect little babies to drink milk or formula, or take in only soft foods that don’t require any chewing. If a big bite, or a fish bone is in there, they could get hurt. But as children grow into adults they should be able to handle bigger bites, process their food themselves, leave out the bitter and dangerous ingredients, while chewing the rest. They can pluck out a bone, or a stalk, and swallow the good parts that remain. To be well fed spiritually it is not enough to just swallow whatever religious and pseudo-religious theory people feed us. We need discriminating filters in place which distinguish the good, the true, and the beautiful so that even bad recipes (i.e., worldviews, systems of theought, theories, ideas, etc.) can be divided into their better and worse parts, and we can find the good kernal of truth underneath the husk, rinds, and gristle that remain. In practice,  the skill of chewing your food means we intentionally evaluate ideas before accepting them. We do not assimilate an idea into our worldview till we’ve considered it’s implications, it causes and effects, and its significance. At first, it may suit your tastes to believe that God the Father Died on the Cross for you and me, but if you probe that idea historically and theologically you’ll find that that’s a declared heresy of the church (Patripassionism) and it obscures the person and work of Christ while misrepresents the doctrine of the trinity. Now, there’s a kernel of truth there, God [Jesus] died on the cross, and that’s a great and beautiful truth that we should all embrace. But we would have to “spit out” the errant additions lest we dilute truth with heresy. When we are in the habit of evaluating ideas before accepting them we get better at distinguishing truth from error, beauty from ugliness, and goodness from evil. It does take some courage to spit out the bad, ugly, and errant elements. And it can take even more courageous humility to swallow the great and beautiful truth when you’ve found it. But overall, we cannot keep our souls well-guarded without this basic filter in place.