Who knows?... Who can tell?: These questions have already been answered. We should spend our days living wisely, enjoying our work, and appreciating God's gifts (Ecclesiastes 2:13–14, 24; 3:22; 5:18). What will happen on this earth has already happened (Ecclesiastes 1:9, 10; 3:15).
like a shadow: Compare Psalms 39:4–6; 90:3–6, 10–12; 109:23; 144:4.