What is the significance of Jesus calling God 'My God' instead of 'Father' on the cross?

When Jesus cried out, 'My God, my God, why have you forsaken me?' He did not refer to God as 'Father' as He normally would. This change in address speaks volumes about the weight of His suffering. In that moment of cosmic darkness (Mark 15:33), Jesus experienced a separation that resulted from bearing the sins of humanity. Historically, throughout His life and ministry, He had perfect communion with the Father. This utterance encapsulates not only His suffering but also the reality of our sin's consequence. It symbolizes the depth of the sacrifice He was making, where He felt the full force of abandonment as part of God’s justice being executed against sin.