Thank you for the question on the interrelationship between the Trinity, “Is there a deal among the Trinity, like a memorandum of understanding? What do you think could be a deal breaker, even if they’re one?”
As one reads the Scriptures, there is no memorandum of understanding or written contract between the Godhead. There isn’t any “deal breaker” among the Godhead.
It is not as though each of the individual Godhead “wrote” up their own “deal” or “consent” and coming together to work out one plan nor are there any clauses that would nullify the “deal.”
As human beings, we are separate individuals with independent thoughts, needs, and desires. To ensure agreement and to avoid misunderstanding, the differing parties agree on a contract. There may even be clauses in our human contract that allows for nullifying the agreement or withdrawing from an agreement.
The Scripture describes God as being One. The oneness is in essence and in being. Godhead has one thought among them, not three separate thoughts. There is no dissension or disagreement within the Godhead, but harmony. They had no need for anything for they are self-sufficient within themselves. There isn’t selfishness or envy between the Godhead. Thus there isn’t any need of “contract” that binds them together or requirement to full their part of the contract. It is not as if one of the Godhead would “walk” away from the being together due to dissatisfaction.
The Scriptures describes the plan of God to share/demonstrate their glory and oneness with created beings. The plan of God is expressed in Ephesians 1 and Colossians 1 for creation.
Ephesians 1 says this, “3 Praise be to the God and Father of our Lord Jesus Christ, who has blessed us in the heavenly realms with every spiritual blessing in Christ. 4 For he chose us in him before the creation of the world to be holy and blameless in his sight. In love 5 he[b] predestined us for adoption to sonship[c] through Jesus Christ, in accordance with his pleasure and will— 6 to the praise of his glorious grace, which he has freely given us in the One he loves. 7 In him we have redemption through his blood, the forgiveness of sins, in accordance with the riches of God’s grace 8 that he lavished on us. With all wisdom and understanding, 9 he[d] made known to us the mystery of his will according to his good pleasure, which he purposed in Christ, 10 to be put into effect when the times reach their fulfillment—to bring unity to all things in heaven and on earth under Christ.
11 In him we were also chosen,[e] having been predestined according to the plan of him who works out everything in conformity with the purpose of his will, 12 in order that we, who were the first to put our hope in Christ, might be for the praise of his glory. 13 And you also were included in Christ when you heard the message of truth, the gospel of your salvation. When you believed, you were marked in him with a seal, the promised Holy Spirit, 14 who is a deposit guaranteeing our inheritance until the redemption of those who are God’s possession—to the praise of his glory” (A searchable online Bible in over 150 versions and 50 languages). Bible citations are from the New International Version.
The closest thing to coming to a “deal breaker” was at the Garden of Gethsemane. Jesus was agonizing over going to the cross and to bear the sins of the world upon himself. As a man, he most likely saw what it was like to see a person nailed to a cross. His death would be even more excruciating that that!
Matthew 26 says this, “42 He went away a second time and prayed, “My Father, if it is not possible for this cup to be taken away unless I drink it, may your will be done” (NIV).
As a human being, he submitted to the Heavenly Father. Could Jesus walked away from his impending death. Theoretically, I would think so as a man, but he knew that if he did that all of humans would perish in their sins. He would have saved himself, but condemned humanity. It is because of his willingness to die such a horrible death that God has exalted his name above every name that at the name of Jesus every knee will bow in heaven and on earth. This sacrifice of the God-Man for humans is beyond words.
SUMMARY: The plan of God is to show the majesty and magnificence of his love and justice for his created beings. Praise God, Jesus didn’t walk away from the plan of God but fulfilled it so that humans can spend eternity with him.
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