Grow up into Him…from whom the whole body…according to the proper working of each individual part, causes the growth of the body for the building up of itself in love. – Ephesians 4:16
When a baby matures, its body parts develop, grow, and work together. Babies move from milk to solid food. The writer of Hebrews compared this development to that of a Christian: “Everyone who partakes only of milk is not accustomed to the word of righteousness, for he is an infant. But solid food is for the mature, who because of practice have their senses trained to discern good and evil. Therefore leaving the elementary teaching about the Christ, let us press on to maturity” (Hebrews 5:13–6:1).
There is a developmental progression in Christian maturity, and one concept depends on understanding another. Elementary principles must be mastered before you can move on to deeper things, but we’re not supposed to dwell on elementary things forever. Spiritual growth takes place on the playing field of life, not in the classroom.
If you never make the connection between the things you learn in Scripture and the way you live your life, you will never mature into anything beyond a Sunday Christian. You are to “work out your salvation with fear and trembling; for it is God who is at work in you, both to will and to work for His good pleasure” (Philippians 2:12-13).
Development is marked by change. When you react to situations by focusing on Christ at work in you, you are becoming a mature believer. When you are mature, you will react, think, and act like Christ because you are being conformed into His image.