God puts a great deal of emphasis on our growth to spiritual maturity.
Check out some of the resources below. When you see what the Bible has to say about maturity, you will realise how important it is to God and how much you benefit from it. Hopefully that will motivate you to “grow in the grace and knowledge of our Lord and Saviour Jesus Christ” (2 Pet 3:18).
Bible passages about growth (pdf) – list of passages with suggested questions.
What spiritual maturity looks like
Christ-likeness. The goal of discipleship is to be like Jesus. What does that mean and is it possible?
12 Characteristics Of A Godly Life – Roy L. Comstock
Why We Need A Different Kind Of “Maturity” In The Church – Carey Nieuwhof
This “Variation On Footprints” describes stages of spiritual growth. (I have not yet discovered who the author was.)