Read what Martin Luther said about the death of God in Luther's Works, volume 41.
“We Christians should know that if God is not in the scale to give it weight, we, on our side, sink to the ground. I mean it this way: if it cannot be said that God died for us, but only a man, we are lost; but if God’s death and a dead God lie in the balance, his side goes down and ours goes up like a light and empty scale. Yet he can also readily go up again, or leap out of the scale! But he could not sit on the scale unless he had become a man like us, so that it could be called God’s dying, God’s martyrdom, God’s blood, and God’s death. For God in his own nature cannot die; but now that God and man are united in one person, it is called God’s death when the man dies who is one substance or one person with God” (LW 41:103–4).