I believe you are misunderstanding that. According to your line of thinking, you are saying that the Son of Man was in heaven existing as God (YHWH) but from heaven God said that He is not a son of man. He said He would not lie or change His mind about these facts.
Numbers 23
19God is not a man, that He should lie,
or a son of man, that He should change His mind.
Does He speak and not act?
Does He promise and not fulfill?
Therefore, the correct interpretation of what you're referring to is in regards to Jesus non literally existing in heaven except for in the mind of, the foreknowledge of, the Logos of, God. This is the best and only way to remove the contractions like the one you introduced above. Jesus existed in heaven in the logos of God (in the bosom or heart of God) and then came down to earth where God's plans manifested by creating a man. (John 1:1-14)
YHWH and Jesus are not the same person. Here is just one clear example of this.
The Lord (Jesus) is at the LORD's(YHWH) right hand.
Psalm 110
1The
LORD[YHWH] said to my
Lord:[Jesus]
“Sit at My right hand
until I make Your enemies
a footstool for Your feet.”
What is your definition of the word "form" in the above passage? Do you consider it to be the outward appearance or shape like Greek lexicons say?
Nope. I understand Christian doctrine. Its not according to my line of thinking, its taught in scripture.
You object to the Christian doctrine of the Incarnation of Christ and the hypostatic unition of His two natures in the One Person of Yahweh the Son.
You quote Numbers for proof. But that text says God can’t lie like men, it says nothing about whether God can be incarnate in human flesh and still be God in heaven.
The logical fallacy causing you to err is caused by the “undistributed middle”, nothing in the text is relevant to the question.
Numbers isn’t discussing God’s Being, who in what way He can manifest Himself.
God is contrasting Himself to men, unlike men who lie and change their minds often, God does not.
Therefore, the text is irrelevant to the question of what forms God can manifest Himself in. Nothing is impossible for God.
AND I cited a text that shows Yahweh in the form of a man with two other “men” and He ate and drank a meal Abraham prepared:
NKJ
Genesis 18:1 Then the LORD [Yahweh] appeared to him by the terebinth trees of Mamre, as he was sitting in the tent door in the heat of the day.
2 So he lifted his eyes and looked, and behold, three men were standing by him; and when he saw
them, he ran from the tent door to meet them, and bowed himself to the ground,
3 and said, "My Lord, if I have now found favor in Your sight, do not pass on by Your servant.
4 "Please let a little water be brought, and wash your feet, and rest yourselves under the tree.
5 "And I will bring a morsel of bread, that you may refresh your hearts. After that you may pass by, inasmuch as you have come to your servant." They said, "Do as you have said."
6 So Abraham hurried into the tent to Sarah and said, "Quickly, make ready three measures of fine meal; knead
it and make cakes."
7 And Abraham ran to the herd, took a tender and good calf, gave
it to a young man, and he hastened to prepare it.
8 So he took butter and milk and the calf which he had prepared, and set
it before them; and he stood by them under the tree as they ate. (Gen. 18:1-8 NKJ)
Yahweh never ceased to be God in heaven even while He was there eating cakes with Abraham on earth. Whether the “three men” were angels or actual men is not revealed in this context, but God was present in one of them even while He remained God in heaven holding all things together.
The Greek Word translated “form” (3444
μορφή) in Phil. 2:5-8 isn’t referring to a physical form:
Meaning: 1) the form by which a person or thing strikes the vision 2) external appearance-Strong's
The “form of God” is a "sinking into the realm of the finite creature, a presence that is visible. The infinite substance of God enters the dimension of the finite creature, but does not actually move from one place to another. Its a "localization" finite creatures can see, and hear but it isn't a "body" like ours or the angels.
Its not holographic, it really is God's Substance made into a visible "form". Recall at Jesus' Baptism, the Holy Spirit appeared in the form of a Dove.
Perhaps water can be used to illustrate this concept. Imagine God is made of water, an infinite Ocean of Water but it exists in a dimension all around us, but we cannot see or feel it.
It cannot be contained in any place, even heaven and heavens of heavens aren't big enough (1 Ki. 8:28).
"But will God indeed dwell on the earth? Behold, heaven and the heaven of heavens cannot contain You. How much less this temple which I have built! (1 Ki. 8:27 NKJ)
So how might God localize a "presence" for finite creatures in heaven, or on earth can see?
Water can manifest itself in various forms, Steam or Cloud or Ice or water.
If God localized some water as a "cloud" or "ice" that people can see, that would be God's "morphe form".