Before this question can be answered, the nature of the Trinity would have to be clearly stated. Not everyone on this site agrees with the orthodoxly defined Trinity. In order to answer, I will state at the outset my understanding of the Trinity. Three Persons share divine nature. The Father and the Son share the one divine nature, with absolute unity of the Spirit in that nature. And in the nature of that nature, there is absolute unity of Spirit. Divine nature and human nature meet in the Person of Jesus Christ.
In the nature of what Deity is, that nature is possessed by a Person, who is named Jesus Christ. He shares that nature with his Father. In relationship, regarding person, his Father is greater than he is. But in the matter of nature, eternal nature, his nature is equal to that of the Father, and he is perfectly one with the Father. As well as this, Jesus Christ, born of woman, also possesses human nature.
The divine relationship is within one Spirit, the divine Person who is the Holy Spirit. All that passes between the Father and the Son, and between the Son and the Father, does so in one Spirit.
Fulness is one of the attributes of Deity. And since that attribute is shared, then it follows that there must be a perfection of unity within Deity, for each shares the attribute of fulness. So what happened when this man, on that cross, cried out in anguish, "My God, my God, why hast thou forsaken me?"
Those words came from a broken human heart, inside a broken physical body, wrenched up and out through this man’s vocal cords into the early afternoon darkness. Here was a dying man crying out to God because of his bearing of sin, in his body. The only way this matter could be resolved was by his dying without having sinned himself. The Bible states that God is too pure to look upon sin, yet Jesus had become sin in order that the wrath of God’s judgment on sin to be suffered by him, personally. That was the once-for-all-time way that sin would be dealt with by God so as to punish sin in such a way that Jesus’ bearing that punishment would suffice for divine justice to be righteously satisfied.
This was determined, agreed upon and accepted by the triune Godhead in unanimous counsel, before they created our material world, for it was foreseen by the wisdom of Deity that it would be necessary. And yet Deity still created humanity.
So, the person on that cross cried out, when briefly forsaken by the Father. Hence Jesus having to address him as “my God” and not “my Father” until a bit later, when unbroken fellowship with the Father was resumed with Jesus giving his spirit to the Father at the point of his physical death. Now, if Jesus’ suffering was only a human matter, then only one (other) human could benefit from that sacrifice. What passed in the darkness, which none other can fathom, was within Deity.
All that we sinful humans should say should be nothing beyond what scripture tells us. For a time, we are told, Jesus experienced what it is to bear the sins of the world, and to have the Father punish him for those. Yet the Father did not abandon him! It was as if the Father turned his back on the Son for a certain time while the Son – of man – was dying. And Jesus knew it. What unspeakable anguish wrenched that cry of dereliction from his lips? He wasn’t just reciting a verse in the Psalms.
My answer to the question is that the heart of Jesus was broken. The Trinity was not broken, for the Trinity had decided before the beginning that this was the only way to deal with sin. The Trinity remained united in carrying out this immense transaction, even though Jesus in his combined deity and humanity knew what it was for a short time to have his fellowship with the Father plunged into experiencing the horror of God’s wrath. And proof that the Trinity had not been broken was in Father, Son and Spirit all playing their part in the resurrection of Christ’s body in the tomb, raising it as a glorified body.
