That Moses requests teaching about this matter of numbering his days shows how difficult a thing it is for us. We don’t do this numbering. We tend to put it to the back of our minds and do arithmetic concerning other things. We forget how few our days are. We don’t calculate their real uncertainty. We are not made to feel how very little of them remain.

Alexander Smellie stated the matter in a very picturesque way. “To the imagination of the young, life seems long. They catch no echo of "the roar of the waves of eternity, as they dash on the shores of time" — so far away those shores appear to be. But the farther I advance in age, the more swiftly and imperceptibly the hours and weeks and years steal on. At the outset of the voyage, I mark my progress by the objects on the river-banks: trees, houses, towering hills. But, later, I have left the river, and am on the trackless sea; and the sea remorselessly impels me on. Soon I shall hear the cry, "Land ahead!" and my voyage of life will be finished and past!”