ďFor ye have not received the spirit of bondage again to fear; but ye have received the Spirit of adoption, whereby we cry, Abba, Father. The Spirit itself beareth witness with our spirit, that we are the children of God:  and if children, then heirs;  heirs of God, and joint-heirs with Christ, if so be that we suffer with him, that we may be also glorified together.Ē  Rm.8:15-17. 

In this passage Paul is using one of the great metaphors in which he describes the new relationship of the believer to God.  He speaks of the Christian being adopted into the Family of God. 

Roman adoption was always rendered more serious and more difficult by the Roman patria potestas.  The patria potestas was the fatherís power over his family; that power was absolute; it was actually the power of absolute disposal and control, and in the early days it was actually the power of life and death. In regard to his father a Roman son never came of age.  No matter how old he was, he was still under the patria potestas, in the absolute possession, and under the absolute control, of his father.  Obviously this made adoption into another family very difficult and a very serious step. 

In adoption a person had to pass from one patria potestas to another.  He had to pass out of the possession and control of one father into the equally absolute control and possession of another.  There were two steps.  The first was known as mancipatio, and it was carried out by a symbolic sale, in which copper and scales were symbolically used. Three times the symbolism of sale was carried out.  Twice the father symbolically sold his son, and twice he bought him back; and the third time he did not buy him back and thus the patria potestas was held to be broken.   

After the sale there followed a ceremony called vindicatio.   The adopting father went to the praetor, one of the Roman magistrates, and presented a legal case for the transference of the person to be adopted into his patria potestas. When all this was completed the adoption was complete.  Clearly this was a serious and impressive step.   

But it is the consequences of adoption which are most significant for the picture that is in Paulís mind.  There were four main consequences. (1) The adopted person lost all rights to his old family, and gained all the rights of a fully legitimate son in his new family.  In the most literal sense, and in the most legally binding way, he got a new father. (2) It followed that he became heir to his new fatherís estate.  Even if other sons were afterwards born, who were real blood relations, it did not affect his rights. He was inalienably co-heir with them.  (3) In law, the old life of the adopted person was completely wiped out.  For instance, legally all debts were cancelled; they were wiped out as though they had never been.  The adopted person was regarded as a new person entering into a new life with which the past had nothing to do.  (4) In the eyes of the law the adopted person was literally and absolutely the son of the new father. 

Roman history provides an out standing case of how literally and completely this was held to be true.  The Emperor Claudius adopted Nero, in order that Nero might succeed him on the throne.  They were not in any sense blood relations.  Claudius already had a daughter, Octavia.  To cement the alliance Nero wished to marry Octavia.  Now, Nero and Octavia were in no sense connected; they were in no sense blood relations; yet, in the eyes of the law, they were brother and sister; and before they could marry the Roman Senate had to pass special legislation to enable Nero to marry a girl who was legally his own sister. Nothing shows better how complete adoption in Rome was. 

This is what Paul is thinking of.  He uses still another picture of Roman adoption. He says that Godís Spirit witnesses with our spirit that we really are children of God.  The adoption ceremony was carried out in the presence of seven witnesses.  Now, supposing the adopting father died, and then suppose there was some dispute about the right of the adopted son to inherit, one or more of the original seven witnesses stepped forward and swore that the adoption was genuine and true.  Thus the right of the adopted person was guaranteed and he entered into his inheritance. So, Paul is saying, it is the Holy Spirit Himself who is the witness to our adoption into the family of God. 

We see then that every step of Roman adoption was meaningful in the mind of Paul when he transferred the picture of our adoption into the Family of God.  Once we were in the absolute possession of sin, in absolute control of our own human nature; but God, in His mercy, has brought us into absolute possession of Himself.  The old life has no more right over us; we begin again anew life; a life with God.    We become heirs of all the riches of God.  If that is so, we become joint-heirs with Jesus Christ, Godís own Son.  That which Christ inherited, and inherits, we also inherit.  If Christ had to suffer we also inherit that suffering, but if Christ was raised to life and glory we also inherit that life and glory. 

It was Paulís picture that when a person became a Christian they entered into the Family of God.  He did nothing to earn it; he did nothing to deserve it; God, the Great Father, in His amazing love and mercy, has taken the lost, helpless, poverty stricken, debt-laden sinner and adopted him into his own Family, so that the debts are cancelled and that unearned love and glory inherited! The price of adoption?  The blood of Christ!