Nevertheless thou art never the nearer Him till thou hast found Him. He is in thee, though He be lost from thee; but thou art not in Him till thou hast found Him. This is His mercy also, that He would suffer Himself to be lost only there, where He may be found, so that thou needest not run to Rome, nor to Jerusalem to seek Him there, but turn thy thoughts into thy own soul where He is hid, as the Prophet saith: Truly thou art the hidden God, hid in thy soul, and seek Him there. (John Climacus)

Soul is an Old English word for our spiritual and/or emotional identity.

The Hebrew scriptures refer most often to nephesh, that which differentiates life from death: desire, activity, passion emotion, and such.

The Gospels write of psuche. Jesus said, "'You shall love the Lord your God with all your heart, and with all your soul, and with all your mind. (Matthew 22:27). In this instance, heart, mind, and soul are each psuche.

There is recent speculation regarding a "God gene" and a region of the brain that is especially active in spiritual people.

My essential identity is as a child of God. Fulfillment is an outcome of living coherently with that identity.