Spiritual growth, based on leading-edge psychological science and research, simply means tuning inwards, consciously!
In other words, spiritual growth, the way I understand it, means a conscious connection, made by your own thinking, will, and intention, with your Higher Self. Acknowledging a higher power, no matter how you call it: God, Allah, Buddha, Christ, or, All There Is. Obviously, we have many names for It; for something that is probably nameless in the sense we use language and words.