Here is an article by Craig Carter that I agree with according to his main point. Carter cites the “specific” reason for the incarnation as human redemption: “God decreed that he would take on flesh for a specific reason. The reason was that without taking on human flesh the eternal, impassible God could not suffer and die for our sins.”

According to Eph. 1.7-10, the bible cites another reason: In him we have redemption through his blood, the forgiveness of our trespasses, according to the riches of his grace, which he lavished upon us, in all wisdom and insight making known to us the mystery of his will, according to his purpose, which he set forth in Christ as a plan for the fullness of time, to unite all things in him, things in heaven and things on earth. (NIV). Since humans have nothing to do with the situation in the heavens (the bible speaks of the heavens as defiled by evil spiritual entities and in need of cleansing), then human redemption is only a glorious part of what God does. God is love and saves us because that is what God, by His nature, accomplishes.

As part of redemption, God reveals His will to us: to bring all things under His loving control (unite in Eph. 1.10). God did not sanction the darkness and chaos of Gen. 1.2 but He allowed and mitigated it by the creation of Light. The Gospel of John picks up this point in Jn. 1.4-5: In him was life, and the life was the light of men. The light shines in the darkness, and the darkness has not overcome it (NIV).Gen. 1.1 speaks of the original creation (without humans). The best way to read the first verse in the bible grammatically is to come to a full stop after verse 1. Therefore, an intercalary between vs. 1 &2 is the best way to see creation initially (and to note that the earth really is 5-15 billion years old).

God created the human’s inhabitable world in 6 days (Ex. 20.11). The first day was separation of light from darkness which, to me seems partially metaphorical. It may have been to separation of the fallen angels from the elect angels (although the evil angels still need to periodically give an account to God (see Job 1.6f.). Therefore, days 2-6 of the creation calendar were to create the livable conditions for the eventual incarnation of Jesus Christ.

The Incarnation of the Impassible God: The Mystery of the Incarnation is Diluted by Theistic Mutualism – Credo Magazine