Understanding children, young adults, and mature adults, as shown in I John, gives us another glimpse of the development of Christian maturity. In fact, training for spiritual maturity needs to begin as soon as the convert passes from childhood to young adult.

We find this explained by John, “I am writing to you, little children, because your sins are forgiven for His name’s sake. I am writing to you, fathers, because you have known Him who is from the beginning. I am writing to you, young men, because you have overcome the evil one.

“I am writing to you, little children, because you have known the Father. I have written to you, fathers, because you have known Him who is from the beginning. I have written to you, young men, because you are strong, and the word of God lives in you, and you have overcome the evil one.” I JOHN 2: 12-14 MEV

So, children, young adults, and mature adults give us the progression to maturity

Children have their sins forgiven and have known the Father. Young adults [men, in these verses] are strong, and the word of God lives in them, and they have overcome the evil one. Mature adults [fathers in these verses] have known Him who is from the beginning. In other words, children have been reborn and know the Father as Daddy. Young adults are strong and have filled their spirits and minds with the word of God. They overcome the enemy in their lives. The mature know God deeply and personally within a close relationship.

Children can only feed on pablum and milk

We are blessed that Hebrews gave us a six-point list of what milk includes.

“…leaving the elementary principles of the doctrine of Christ, let us go on to maturity, not laying again a foundation of: [MEV switching to KJV]

1. repentance from dead works, 
2. of faith toward God, 
3. of the doctrine of baptisms, 
4. and of laying on of hands, 
5. of resurrection of the dead, 
6. and of eternal judgment.” [Hebrews 6: 1-2 MEV and KJV]

Consider what’s included in this list. For churches focused on the great commission and world evangelism, this is all that is offered in many congregations. The preaching rarely, or never, gets past this level of instruction. Now I agree, discussions of sin, the Blood, the Cross, and so on are a large part of this. I guess they’re covered in numbers 1 & 2. But I think the point is obvious.

Young adults have a great deal to learn and experience in addition to spiritual warfare

But the main thing remains clear: spiritual warfare; sanctification; deliverance; forgiveness; spiritual gifts, callings, and offices; freedom from sin; putting off the old self and putting on the new; works of the flesh and the fruit of the Spirit; the end times and the rapture; and most of the things which affect believers in our daily walk with the Lord are not covered in milk. They are all part of solid food. Just out of curiosity: ‘How many of you are taught these things in your church?” My assumption is that if they are taught at all, it’s in the context of a small home Bible study. But I could be far off target here.

“You have overcome the evil one.” Please notice that this is past tense. John assumes, as do I, that you will get to the place where your spiritual warfare skills become habitual, and even subconscious, ways of reacting to the events in your lives. This is a similar process to being taught to instantly recognize counterfeit money. You are trained so thoroughly in what the real thing looks like, smells like, feels like, and wears like that a counterfeit is simply obvious. Similarly, you learn to know the Lord so well and what true Christianity is, that the enemy is quickly recognized and neutralized.

Mature adults are comfortably at peace because they have come to know the Lord, personally

As Jesus prayed in John 17, “This is eternal life: that they may know You, the only true God, and Jesus Christ, whom You have sent.” JOHN 17:3 MEV They have entered the Sabbath rest, trusting in the One they know is able. This is the main task of the Bride of the Messiah. It’s a wonderful way to live.