One pastor said on a podcast that this shows church is for all generations, not just grandmas and grandpas! Since it is mentioned somewhere that Israel is God’s firstborn, it also demonstrates the progression of God’s salvation for all mankind, from God to Abraham to Jesus and to all nations.
ishmael was abrahams first born also but never received the inheritance of Abraham
“For it is written, that
Abraham had two sons,
the
one by a bondmaid,
the other by a freewoman…. Which things are
an allegory: for these are the two covenants;
the
one from the mount Sinai, which gendereth to bondage, which is Agar. For this Agar is
mount Sinai in Arabia, and
answereth to Jerusalem which now is, and is in bondage with her children.
But
Jerusalem which is above is free, which is the mother of us all.
…Nevertheless what saith the scripture?
Cast out the bondwoman and her son: for the son of the bondwoman shall not be heir with the son of the freewoman.
So then,
brethren, we are not children of the bondwoman, but of the free.”
Galatians 4:22, 24-26, 30-31 KJV
“For
ye are not come unto the mount that might be touched, ( Sinai and the ot law )
and that burned with fire, nor unto blackness, and darkness, and tempest, And the sound of a trumpet, and the voice of words; which voice they that heard entreated that the word should not be spoken to them any more: (For they could not endure that which was commanded, And if so much as a beast touch the mountain, it shall be stoned, or thrust through with a dart: And so terrible was the sight, that Moses said, I exceedingly fear and quake
But
ye are come unto mount Sion, and unto the city of the living God, the heavenly Jerusalem, and to an innumerable company of angels, To
the general assembly and church of the firstborn, which are written in heaven, and to God the Judge of all, and to the
spirits of just men made perfect,
And to Jesus the mediator of the new covenant, and to the blood of sprinkling, that speaketh better things than that of Abel.
See that ye
refuse not him that speaketh. For if
they escaped not who refused him that spake on earth, much more
shall not we escape, if we turn away from him that speaketh from heaven:”
Hebrews 12:18-25
Who spoke from heaven ?
John 3:31-36