I. There are four Uses of Illustrations.
1. They win and hold attention. The ear is quickened to interest by a story; the eye is arrested by the picture or the chalk mark. Nothing awakens and retains the interest more than the illustration, whether heard or seen.
2. They aid the apprehension. The statement of a truth is made plain where it is illustrated, as the rule in arithmetic is seen more clearly in the light of an example; and the definition of a scientific word in the dictionary by the picture accompanying it.
3. They aid the memory. It is not the text, nor the line of thought, but the illustrations, which keep the sermon or the lesson from being forgotten.
4. They awaken the conscience. How many have been aroused to conviction of sin by the parable of the Prodigal Son; and what is that but an illustration? So, many, like Zinzendorf, have been awakened by some picture of a Bible scene. Mr. Moody’s stories have sent the truth home as deeply as his exhortations.
II. There are four Classes of Illustrations.
1. Those which depend upon the sight, and derive their interest from the pupil’s delight in seeing. Such are maps, pictures, diagrams, etc., and when drawn in presence of the scholar, though ever so rudely, they have an increased interest and power.
2. Those which depend upon the imagination. At no period in life is the imagination as strong as in childhood, when a rag doll can be a baby and a picture has real life. Thence come “word-pictures,” fairy stories, imaginary scenes, etc., as illustrations of the lesson.
3. Those which depend upon comparison. To see resemblance in things different, or the correspondence between the outward and the spiritual, is as old as the parable of the sower, and the miracle of the loaves. “The likes of the lesson” form a fruitful field for the use of illustration.
4. Those which depend upon knowledge. More than for anything else children are eager to know; and the story has an added value which is true. History, science, art, and indeed every department of knowledge will furnish illustrations of spiritual truth.