No, not Christ divide, but rather the two "in Christ" as One. The two are biblical Israel and the gentiles, but spiritually they are the dead and the living in new life in Christ - this is salvation, to those who were lost (dead).
Trying to collect where the questions are instead of rambling. Not by any means saying you are wrong or arguing a point but presenting questions.
1) reference to Hebrews 12:23
[23] 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,
2) you say the OT saints are the dead in Christ while we are Spirit (the alive in Christ). Yet the promise was the Spirit...the supernatural birth...a seed that continues which is Christ.
Colossians 3:2-3 Set your affection on things above, not on things on the earth. [3] For ye are
dead, and your life is hid with Christ in God.
Matthew 3:9-12
[9] And think not to say within yourselves, We have Abraham to our father: for I say unto you, that God is able of these stones to
raise up children unto Abraham. [10] And now also the axe is laid unto the root of the trees: therefore every tree which bringeth not forth good fruit is hewn down, and cast into the fire. [11] I indeed baptize you with water unto repentance: but he that cometh after me is mightier than I, whose shoes I am not worthy to bear: he shall baptize you with the Holy Ghost, and with fire: [12] Whose fan is in his hand, and he will throughly purge his floor, and gather his wheat into the garner; but he will burn up the chaff with unquenchable fire.
God is able of these stones to raise up children unto Abraham. God did and was always going to which is the very reason the stones would have cried out if He had held His peace.
The promise of children made to Abraham not through or by flesh but by the supernatural: GOD. John 14:26-27
[26] But the Comforter, which is the Holy Spirit, whom the Father will send in my name, he shall teach you all things, and bring all things to your remembrance, whatsoever I have said unto you. [27]
Peace I
leave with you, my peace I
give unto you: not as the world giveth, give I unto you. Let not your heart be troubled, neither let it be afraid.
...stones raised up as Children of the promise unto Abraham.
Luke 5:34
[34] And he said unto them, Can ye make the children of the bridechamber fast, while the bridegroom is with them?
The New lump: 1 Corinthians 5:5-7
To deliver such an one unto Satan for the destruction of the flesh, that the spirit may be saved in the day of the Lord Jesus. [6] Your glorying is not good. Know ye not that a little leaven leaveneth the whole lump? [7] Purge out therefore the old leaven, that ye may be a new lump, as ye are unleavened. For even Christ our passover is sacrificed for us:
Spirit Romans 11:16
[16] For if the firstfruit be holy, the lump is also holy : and if the root be holy, so are the branches.
^ until the fullness of the Gentiles comes in...in to what? Don’t understand how is a new lump + Gentiles or a new lump plus Israel when the word said they became One the separation torn.