Unfortunately, we in the modern church age have defined maturity much different than that of our forefathers, especially those of the New Testament age. Paul, in speaking to the Corinthian believers confronted them about their immature walk when he said "what causes quarrelling and strife among you?" He was saying in effect, "don't you know when you focus on the outward things such as obeying certain rules, rituals, and traditions of men, you are acting as mere "babes."
Paul wanted the believers of his day to know the difference between maturity and immaturity in their Christian lives. Today, many Christian leaders of various denominations, organizations, and other sects still walk in the "carnality" of trying to hold to certain accepted behaviors, and then have the audacity to equate obeying these "traditions" of the church as Christian maturity!
True maturity as a Christian has to do with a progressive decreasing of US, as Christ in US increases through personal revelation. It has nothing to do with with the separatist theology which teaches that Christ is "over there" and you need to beg Him to come into your particular situation or need, or you need to straighten up and fly right, the teaching that is rampant in the modern day organized church, and worse, is generally accepted as normal Christian living!
Paul said true maturity "in Christ" is just that, being "In Christ!" I no longer live (have desires, hopes, plans, dreams or a life of my own) because he has become my life and is becoming more and more real to me as my only life!
Many believers in churches all over the world truly desire ALL Christ has for them in this life, but when they see the only way to this "in HIM" life is the same path Paul took, that is "counting ALL things loss in comparison to the surpassing greatness of knowing Christ as LORD" they hesitate and shrink back because they don't understand the concept of "losing to gain" that Jesus himself so often spoke of.
When we get saved Jesus makes His home in our hearts! But that is only the beginning! As we press on into maturity, allowing God to bring us to the place, most often through extremely difficult circumstances and trials, of forsaking all so that He becomes our all, we are progressively swallowed up (decreased) by His life, with the goal being a "resurrection" walk, such as what Paul referred to in the Bible, that no longer cares about anything this present world has to offer. It's now a walk in which Christ has become our very life!
We move from our Romans 7 cry of "who will deliver me from the body of this death" onto the Romans 8 personal revelation of "There is now therefore no condemnation to those who are in Christ Jesus, for the Law of the Spirit of Life has set me free from the law of sin and death!" Praise God, Paul learned through his own trying to "do" the Christian life that, not only could he not live his Christian life by his own strength, but was never meant to! And neither can we! In fact, the only person who can live the Christian life is Christ! Our only purpose (see Romans 12:1-4, John 15, Hebrews 4) as "containers" of Him are to "Yield" our "way to Him as He (pours) reveals Himself in us! That's it!
This my friends is the only true maturity and it has nothing to do with with anything we do, not what position we hold, how educated we are, whether we are pastors, ditch diggers, or anything else that involves us, absolutely nothing! Galatians 2:20 says it all......... " I no longer live, Christ lives in me!"