an expression used by St. Paul in reference to the present and prospective privileges of Christians. ( Romans 8:15 Romans 8:23 ; Galatians 4:5 ; Ephesians 1:5 ) He probably alludes to the Roman custom by which a person not having children of his own might adopt as his son one born of other parents. The relationship was to all intents and purposes the same as existed between a natural father and son. The term is used figuratively to show the close relationship to God of the Christian. ( Galatians 4:4 Galatians 4:5 ; Romans 8:14-17 ) He is received into Gods family from the world, and becomes a child and heir of God.