“my firstborn.” When God said that Israel was His “firstborn son,” He was opening the door for others besides Israel to be accepted into His family. We see this to a small degree in the Old Testament when Gentiles become an important part of Israelite society (cp. Rehab the Canaanite, Ruth the Moabitess, Uriah the Hittite), and Jesus Christ spoke of it too: “And I have other sheep that are not of this fold. I must bring them also, and they will hear my voice. And there will be one flock with one shepherd” (John 10:16). But the door was fully opened after the Day of Pentecost when God made “one new person” out of both Jews and Gentiles (Eph. 2:11-14).