Ga 4:1-31. THE SAME SUBJECT CONTINUED: ILLUSTRATION OF OUR SUBJECTION TO THE LAW ONLY TILL CHRIST CAME, FROM THE SUBJECTION OF AN HEIR TO HIS GUARDIAN TILL HE IS OF AGE. PETER'S GOOD WILL TO THE GALATIANS SHOULD LEAD THEM TO THE SAME GOOD WILL TO HIM AS THEY HAD AT FIRST SHOWN. THEIR DESIRE TO BE UNDER THE LAW SHOWN BY THE ALLEGORY OF ISAAC AND ISHMAEL TO BE INCONSISTENT WITH THEIR GOSPEL LIBERTY.

      1-7. The fact of God's sending His Son to redeem us who were under the law (Ga 4:4), and sending the Spirit of His Son into our hearts (Ga 4:6), confirms the conclusion (Ga 3:29) that we are "heirs according to the promise."
      the heir-- (Ga 3:29). It is not, as in earthly inheritances, the death of the father, but our Father's sovereign will simply that makes us heirs.
      child--Greek, "one under age."
      differeth nothing, &c.--that is, has no more freedom than a slave (so the Greek for "servant" means). He is not at his own disposal.
      lord of all--by title and virtual ownership (compare 1Co 3:21, 22).

JFB.