I like what Paul says in Romans 8:15, “For you did not receive a spirit that makes you a slave again to fear, but you received the Spirit of sonship. And by him we cry, ‘Abba, Father.’” What a transformation those who trust in Jesus Christ experience - from fear to freedom in a powerful new relationship of adoption into sonship. 

 

F.F. Bruce suggests we take care not to see things through our contemporary cultural understanding, rather than the Greco-Roman culture of Paul’s day. He writes: “The term ‘adoption’ may have a somewhat artificial sound in our ears; but in the Roman world of the first century AD an adopted son was a son deliberately chosen by his adoptive father to perpetuate his name and inherit his estate; he was…not in the smallest degree inferior in status to a son born in the ordinary course of nature, and might well enjoy the father’s affection more fully and reproduce the father’s character more worthily.” 

 

It is not clear whether it is the result of our receiving the Spirit of sonship that causes us to cry out, “Abba, Father.” Or when we cry out, “Abba, Father,” the Spirit bears testimony with our spirit that we are God’s children. Basically it doesn’t matter. We receive the Spirit of sonship when we trust in Jesus Christ. The Holy Spirit knows when we have received Jesus Christ and bears witness with our spirit that we are God’s children. 

 

Once that relationship is established it is proper for us to call God the Father, our Father, and say “Abba,” as an expression of intimacy and warmth, such as a child would express to a loving father.