<p>4:4 <i>But when the fullness of the time came</i>- As if God carefully set a time period for the operation of the Mosaic law, just as He brought it into operation at a specific point 430 years after the covenant with Abraham (3:17). This idea of a specific time period is in keeping with the analogy regarding a child being set a period of time to live under governors, until he receives the inheritance as a young adult. I discussed under Galatians 3 the whole reason why the Law was given; its intention was to highlight sin and grace, and to make men throw themselves upon God's grace in Christ when this appeared in the person of the historical Jesus. The time period was optimal for that purpose to be achieved; yet many preferred the Law and effectively rejected Jesus, or like the Galatians, accepted Him but then went to the Law. That shows how God carefully set up a potential, but people preferred not to make use of it. He prepared and put them through a course of education, if you like; but they didn't engage with it, didn't get it, and went their own ways.</p><p><i>God sent His Son, born of a woman, born under the law</i>- The purpose for this was &quot;that we might receive the adoption of sons&quot; (:5). Paul has just explained in chapter 3 that by baptism into Christ, we are counted as Him. All that is true of Him becomes true of us; He was Abraham's seed, so are we. Paul is explaining how the heirs came to receive the inheritance. We became the full sons of God because God's Son was born and was human. As our representative, we can identify with Him by baptism (3:27-29) and thus become Him, as it were. Again note that the implication of the argument is that in some sense, we are &quot;heirs&quot;, inheritors, in that we are those who have now received the inheritance. This does not preclude a future, literal receipt of the land inheritance; but we have received the spiritual blessings promised Abraham, which Acts 3:26 interprets as the turning away of our hearts from sin.</p>