How can we bridge the gap between a newborn believer and a mature believer?

As Christians, our focus is to grow spiritually after salvation till we all come unto the measure of the stature of the fullness of Christ Ephesians 4:12-13

Also, God desires that we are sanctified wholly in spirit, soul, and body according to 1 Thessalonians 5:23 so we can the nature and character of Christ

Colossians 3:16