'Mature' in the Bible

Go, gather the elders (tribal leaders) of Israel together, and say to them, ‘The Lord, the God of your fathers, the God of Abraham, of Isaac, and of Jacob, appeared to me, saying, “I am indeed concerned about you and what has been done to you in Egypt.

Yet we do speak wisdom among those spiritually mature [believers who have teachable hearts and a greater understanding]; but [it is a higher] wisdom not [the wisdom] of this present age nor of the rulers and leaders of this age, who are passing away;

Brothers and sisters, do not be children [immature, childlike] in your thinking; be infants in [matters of] evil [completely innocent and inexperienced], but in your minds be mature [adults].

until we all reach oneness in the faith and in the knowledge of the Son of God, [growing spiritually] to become a mature believer, reaching to the measure of the fullness of Christ [manifesting His spiritual completeness and exercising our spiritual gifts in unity].

All of us who are mature [pursuing spiritual perfection] should have this attitude. And if in any respect you have a different attitude, that too God will make clear to you.

We proclaim Him, warning and instructing everyone in all wisdom [that is, with comprehensive insight into the word and purposes of God], so that we may present every person complete in Christ [mature, fully trained, and perfect in Him—the Anointed].

Epaphras, who is one of you and a bond-servant of Christ Jesus, sends you greetings. [He is] always striving for you in his prayers, praying with genuine concern, [pleading] that you may [as people of character and courage] stand firm, [spiritually mature] and fully assured in all the will of God.