1 Corinthians 14:20

Brother and sisters, do not be children (immature, childlike) in your thinking; be infants in (matters of) evil (completely innocent and inexperienced), but in your mind be mature (adults).

Our age doesn’t matter; we will still be maturing and controlling our thoughts. We are growing and learning from God and His word, so our thoughts will develop toward focusing on the instructions from God. We will know what to avoid looking at, listening to, and seeing to keep ourselves innocent of evil.