'Mature' in the Bible

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.