But you shall laugh. Thus it is written. And because God's Word also had recourse to human words in order to express what shall one day be when all shall have been—that is why a mystery of eternity also lies deeply hidden, but real, in everyday life; that is why the laughter of daily life announces and shows that one is on good terms with reality, even in advance of that all-powerful and eternal consent in which the saved will one day say their amen to everything that he has done and allowed to happen. Laughter is praise of God because it foretells the eternal praise of God at the end of time, when those who must weep here on earth shall laugh.
KARL RAHNER The Great Church Year: The Best of Karl Rahner’s Homilies, Sermons, and Meditations