So the wise teacher, in preparing the lesson, knows that he must first reach that ledge himself; must repeat the journey over and over until he has learned the easiest way for little feet; must make ladders with rounds close together; must spread sand on slippery places and stretch ropes along the edge of the cliff. He, too, lays in supplies of stories and pretty parables, not, however, in the form of powder, to make a show, but (if this is not too severe a twist of the simile) as dainty food to keep the young travelers fresh and hearty. He, too, has facts and figures and arguments and evidences, not, however, as cannon-balls, but in the shape of iron bridges and railings and ropes, that the way may be solid and safe. There are some teachers that do not study at all. It is as if a will-o'-the-wisp should undertake to guide one on an important journey. Those teachers are going they know not whither, over they know not what road, for what purpose they have not the slightest idea, and land always in a bog. Emphatically, the teacher that is not always climbing himself will leave his class on a very dead level indeed. He should be reaching down and pulling them up, but he is soon compelled to stand where they are and push, and ends with believing his "level best" to lie along the smooth road of the easy-going valley. The teacher who ceases to grow ceases to teach. That is why a Sunday-school lesson cannot be crammed. That is why preparation for it must extend all through the week. Growth cannot be ordered offhand. It comes from Father Time's shop, and he is a deliberate workman. You will lose your hold on your class if each Sunday hour does not begin with you a little above them, and end with them at your level. This advance cannot be won Saturday night, or during the space between the first and second bells for Sunday-school. Such a spasmodic leap ahead will leave you too much out of breath even to tell them to come on.