A prairie fire was whipped along by the wind so fast that it overtook all creatures in its path. One family, realizing the impossibility of outrunning the blaze, began a back fire and then covered themselves with earth as they lay in the middle of the already burned-out circle. The roaring fire met the back fire and burned only up to the edge of the burned-out place; then went around it, continuing its hungry race. The family was saved. They knew the only safe place was where the fire had already burned.
God's judgement is like that fire. It has already touched down at one point in history — when Jesus was judged on the cross for our sins. God's judgement will come again and consume the whole earth and its people. The only safe place for us will be with Jesus Christ, who already suffered the judgement for us.