This quote is from Moltmann’s The Spirit of Life:
Because of God’s cross, creation already lives from God, and will be transformed in God. Without the cross of Christ this vision of ‘the world in God’ would be pure illusion. The suffereing of one, single child would prove it to be so. Without perception of the suffering of God’s inexhaustible love, no pantheism, no panentheism can endure in this world of death. They would very soon end up in pan-nihilism (213).