Summary: The Christian life is more than a list of do's and don't's; it is a relationship wherein we have responsibilities.
John Newton, author of the beloved hymn Amazing Grace, was an only child who lost his mother when he was seven. At the age of eleven, he went to sea as a sailor and became involved in the inhuman African slave trade. He was soon hardened by his surroundings. He outdid his companions in immorality, vulgarity and blasphemy against God. When twenty-three, his ship was caught in a severe storm. When he thought his life was in danger, he cried out to God for mercy. He was marvelously saved. Not wanting to ever forget the grace of God who saved him from the depths of his sin, he penned the words to that beloved song. He later inscribed the words of Deuteronomy 15:15 above his mantel: “And you shall remember that you were a bondman in the land of Egypt, and the Lord your God redeemed you.”
I often wonder if we truly realize our position in Christ as his children. The Bible says we are sons and daughters of God. Because of this, there are certain responsibilities we have. Just as there are certain responsibilities children have in their normal family, so there are in the spiritual family. Just as others can assess what kind of family we come from by our actions and behavior, so they should be able to tell something about our spiritual family as well. Just as good moral and ethical behavior can point others to good parents, so our spiritual actions should draw others to our heavenly father. It is indeed the highest privilege to be called sons and daughters of God, and at the same time it places the utmost of responsibility upon us.
In the ancient world, the division between childhood and adult was more definitive than in most societies today. There was usually a prescribed age when a boy would enter adulthood. A ceremony usually accompanied this period. It was the time when the boy would come of age and thereby take on the responsibilities and privileges of adulthood.
In the Jewish culture, a boy was under his father's control until the age of twelve. At the bar mitzvah ceremony, the father would pray; “Blessed be thou O God who hath taken from me the responsibility of this boy,” and the boy would pray; “O my God and God of my father, on this solemn and sacred day which marks my passage from boyhood to manhood, I humbly raise my eyes unto Thee and declare with sincerity and truth that henceforth I will keep Thy commandments and undertake to bear the responsibility of my actions toward Thee.”
In the culture of Greece, a boy was under the father's control until about age eighteen. Then a festival was held in which the boy was declared a type of cadet. He then undertook special responsibilities to his clan or city state for a period of two years. During this ceremony, his long hair was cut and offered to the god Apollo.
In the Roman culture, the boys would take their toys and offer them in sacrifice to the gods as a symbol of putting childhood behind them.
Paul compares the child to a slave. As long as the child was such, he lived in conditions not much different from the slave. He was an heir by legal right but not an heir in fact. He was under the authority of slaves established by his father. They acted as his guardians. They did this until he was grown. But at the date set by the father, the child's status changed dramatically. Now he was an heir in fact.
When we come to faith in Christ, we become sons and daughters of his with all the ensuing responsibilities. A part of this usually involves baptism and church membership. When we enter this covenant with him, we too take on certain responsibilities.
I. THE SOURCE OF OUR SONSHIP
The source of our sonship is the true Son himself, Jesus Christ. Just as the human father established the time when his son would come of age, so God set the time when he would send his Son. Paul says it was in the fullness of time. The work of Jesus provided the guarantee that believers would become joint heirs with him. Many lived before this time trusting by faith in God but never received the fullness of God's promise for Christ did not come. But in the fullness of time, God sent him.
The fullness of time refers to a period of completion in God's timetable. We can see how the world was made ready for his appearance. God gave the law to show people how utterly helpless they were to live up to God's standards. This accomplished its purpose. The time was right religiously for God to send Jesus. The Israelites had spent seventy years in Babylonian captivity. After hundreds of years of rebelling against God, this seemed to teach them a lesson. They put away their other gods and forsook idolatry. The time was right culturally. Alexander the Great's escapades spread the Greek language throughout the known world. This would give a common language to Christians as they spread the gospel message during the first centuries. There was also economic and political stability. The Romans provided this. They built a magnificent system of roads that would allow the early Christians to travel on.