The key to understanding this is to realize that death is not the end of existence for an embodied spirit such as a human being. The spirit survives death. However, when a human being dies, even though the spirit survives death, we say that a person – not a body – died. Christ is one Person who is both God and man. When he was crucified, the Person of Christ, who is the Second Person of the Trinity, died. However, he did not cease to exist. His soul separated from his body and was later reunited at the Resurrection. Because the Second Person did not cease to exist, the Trinity continued to exist during the time between the Crucifixion and the Resurrection.
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