Gal 4:1 Now I say, [That] the heir, as long as he is a child, differeth nothing from a servant, though he be lord of all; Paul is continuing his illustration of the spiritual immaturity of those who insist on remaining under the Law by using the Roman Law and custom of a son ‚Äúcoming of age.‚ÄĚ The father in the Roman household chose the time for the coming of age of the heir. This was different than the Jews or Greeks. It was usually celebrated on March 17 with a event known as Liberalia. The son received an adult toga and entered into adult responsibilities.
Gal 4:2 But is under tutors and governors until the time appointed of the father. So here Paul focuses on the legal rights and status of children. He makes the comparison to the Law as offering that the Law had a function to keep us out of trouble and disciplining us during our ‚Äúimmaturity‚ÄĚ until God offered us ‚ÄúMaturity‚ÄĚ through our salvation by grace. God set the time for determining when to terminate our guardianship and make us children and heirs by faith. Faith then initiates the believer into maturity and full rights.