For everyone who partakes only of milk is unskilled in the word of righteousness, for he is a babe. But solid food belongs to those who are of full age, that is, those who by reason of use have their senses exercised to discern both good and evil. (Hebrews 5:13–14—NIV)

Do you recall eighth grade awkwardness? It was common in my generation to hear one adolescent admonish another with, "Act your age, not your shoe size!" It was a biting expression of disdain for some exhibit of immaturity. It was a tacit recognition that maturity and age are not synonymous. There is nothing so seemly as age and maturity on a parallel track nor so shocking as age and maturity out of balance.

Our text teaches that spiritual maturity can be judged just as simply as physical and emotional maturity. The phrase "of full age" is actually the term for perfection. The work of the Holy Spirit in the life of the believer is to produce maturity in every aspect of life. There is nothing wrong with the Holy Spirit ministering the sincere milk of the Word to someone who is freshly born again. Babies are designed to crave milk, to know what to do with it, and grow by it (2 Peter 2:2).

Something would be wrong if, as a child grows, he only exhibits a preference for milk, and in fact, it is all he can handle. Infant life is to move on toward maturity and to be weaned from what was designed for immaturity to that which is designed for maturity. Our text describes the maturing saint’s new diet as solid food. Though we never outgrow a tall glass of refreshing milk, and now and then we are placed on a liquid diet in order to recover from some surgery or setback, there is something to be said about the satisfaction of a good meal, well-balanced, and filled with sensory and celebratory color, aroma and taste. No infant can appreciate the richness of a Thanksgiving repast; he has all the richness he can handle in his mother’s milk.

Similarly, believers must graduate in their taste and thirst for something richer in their spiritual diet. This richness can only be tolerated by practice, experience, appreciation and maturity (our text says "exercised"). The recipients of the book of Hebrews were regressing in their maturity. Paul had similarly admonished the Corinthian church, "I fed you with milk and not with solid food; for until now you were not able to receive it, and even now you are still not able; for you are still carnal. For where there are envy, strife, and divisions among you, are you not carnal and behaving like mere men?" (1 Corinthians 3:2–3) There is nothing wrong with milk for every age, but there is more that God intended for His children to enjoy. Carnality had robbed the Corinthian church of maturity and they had not learned the basic lessons of humble servanthood, forgiveness, and love for the brethren. They were still acting after the flesh. Until these primary, godly behaviors were understood, embraced and exercised they needed to remain on a basic liquid diet.

As the author of Hebrews reminds us, "solid food belongs to those of full age, that is, those who by reason of practice have their senses exercised to discern both good and evil." The perfection which the Holy Spirit desires to produce in the believer is one which can distinguish and decide between that which is good (praiseworthy and beautiful) and that which is (by nature) evil. Such wisdom comes from practiced experience and is also a gauge by which to judge (for oneself and for others) success in spiritual maturing.

Thoughts worth pondering: Have you recently observed any displays of immaturity in your life? How mature in the faith have you been today? Can you name an area in your life where you are still craving the basic milk of Scriptural truth in order to suppress the carnal desires? What godly behaviors do you need to exercise in order to receive victory from God so that you may move ahead in maturity?