"part of Himself" - "of one substance"
... God’s love for the world was not manifest because He sent His Son, but because He loved the world He sent His Son into the world that divinity clothed with humanity might touch humanity, while divinity lay hold of infinity. Though sin had produced a gulf between man and his God, divine benevolence provided a plan to bridge that gulf. And what material did He use? A part of Himself.... 6LtMs, Lt 36a, 1890, par. 11
This phrase was used by Ellen several times where “part of Himself” is obviously NOT literal. However, in this quote, we must also consider the word “material”. How did God bridge the sin-caused-gulf between Heaven and Earth(think: Jacob's Ladder)? Answer: With His Divine Son(the Ladder-Jn1:51). God used material from Himself when He"brought forth"(Pr8:24,25) Christ, from His bosom (Jn1:18) as His "only begotten Son"(Jn1:18;3:16) -- the "firstborn of every creature"(Col1:15).
And, since God used material from Himself to bring forth His Divine Son, Christ could rightly “claim that he and the Father were of one substance, possessing the same attributes.”
The Jews had never before heard such words from human lips, and a convicting influence attended them; for it seemed that divinity flashed through humanity as Jesus said, “I and my Father are one.” The words of Christ were full of deep meaning as he put forth the claim that he and the Father were of one substance, possessing the same attributes... ST November 27, 1893, par. 5
Like Christ is “a part of ” God, in a similar way, Eve was “a part of ” Adam, for we know that Eve was formed from a rib of Adam:
Love, gratitude, loyalty to the Creator—all were overborne by love to Eve. She was a part of himself, and he[Adam] could not endure the thought of separation. If she must die, he would die with her... EP 25.5
Desiring to live by every word that comes from the mouth of Jehovah (Deut8:3; Mt4:4)
-Sid Nash: 1/12/2023. Latest version: http://sidnash.org/docs/APartOfHimself.html