1 Corinthians 14:20

"Brothers, do not be children in your thinking. Be infants in evil, but in your thinking be mature."

God calls believers to maturity. We treat adults and babies very differently. When I was a baby I was nursed and changed constantly. I did nothing for myself. But as an adult, I'm now expected to feed myself, clothe myself, work for my housing etc. Likewise, in spiritual adulthood, we should be able to feed ourselves. We should not expect to be bottle fed. We can't just depend on others to tell us what to think about God's Word. We must work to read God's Word for ourselves and actively let it make our thinking spiritually mature. We should think maturely, and when we worship, we should worship with our minds engaged.

Paradoxically, part of being a mature believer is becoming an infant in matters of evil. God calls believers to innocence. With regards to the experience of evil, we should be as ignorant as newborns. We should not seek to feel what sin is like. Contrary to our responsibility to understand God’s word/truth to the fullest of our abilities, we should seek to know as little as possible of sin experientially. Experts on counterfeit money do not study counterfeit bills. Instead they become so intimately familiar with true bills, that when presented with a fake they can identify it immediately. As believers we should seek after holiness so diligently, that when presented with the deceptive nature of sin we can immediately recognize and reject it, even though experientially, we know nothing of it.