The selection of the theme for preaching is to be determined chiefly by the power of the Word to lay hold of the conviction of the preacher. Or, if the subject is prescribed, as when one is lecturing through a book of the Bible, the points to be treated are to be determined in this way. Sometimes, as a preacher reads the Word, a text will leap from the page, so to speak, and, fastening on the mind, insist on being preached upon. A sermon on such a text is nearly always successful; and a wise man will, therefore, take care to garner such texts when they occur to him. He will underline them in his Bible, or, better still, enter them in a note-book kept for the purpose, adding a few words perhaps to indicate the first lines of thought which have occurred to him. These notes may be multiplied from time to time; and, when the minister turns to a page which has been thus filled, he will often find his sermon nearly made to his hand.[30] Dr. Wendell Holmes tells of Emerson that he kept such a note-book for subjects on which he might lecture, and for suggestions of lines of thought which he might follow out. He called it his Savings Bank, because, though the payments into it were minute, they gradually swelled to riches; and passages which his hearers and readers supposed to be outbursts of sudden literary creation were really the results of slow accumulation. If this was necessary for even a genius like Emerson it will be far more necessary for the ordinary man. The gold of thought has generally to be collected as gold dust.
2. But this already brings me to the second stage of this natural history, which is, that the preacher must be a master of Human Words. The message from God which we carry is to become a message to men, and therefore we must know how to introduce it successfully to their notice. Strong as our own conviction may be, yet it may be crude and formless; and, before it can become the conviction of others, it must take a shape which will arouse their attention. It may belong to a region of thought with which they are unfamiliar, and it has to be brought near, until it enters the circle of their own ideas.
This is the problem of the composition of the sermon, whether this means the writing of it out or the arrangement of the materials in the memory in preparation for delivery. And many rules might be given to help at this point.
One often recommended is to keep the audience in view to which the composition is to be addressed. If by this is meant that the writer, as he sits at his desk, should try to conjure up in his imagination the benches of the church and their occupants, I do not know whether it is a practicable rule or not. But if it means that the preacher, as he composes his sermon, should keep in view the circumstances of his hearers--their stage of culture, the subjects in which they are interested, the Scriptural attainments which they have already made, and the like--it is one of the prime secrets of the preacher's art, and I will return to speak of it more fully in a subsequent lecture. I once heard Mr. Spurgeon preach a characteristic sermon on an unusual text. It was on these words in Hosea: "I was unto them as they that take off the yoke on their jaws, and I laid meat unto them." To illustrate the first clause he drew a graphic picture of a London carter in Cornhill loosening the harness, when his horse had surmounted the incline, taking the bit out of its mouth, and fastening on the corn-bag; and he applied the second clause with humorous wisdom to the behaviour of preachers. As the carter in the stable "lays" the hay to his horse, so the preacher has to "lay" the food to the congregation. The carter must not put the food too high, where the horse cannot reach up to it, nor too low, where it cannot get down to it, but just where it can seize and devour it with comfort. So the preacher must neither pitch his message too high, where it will be above the comprehension of the congregation, nor too low, where it will not command their respect, but just where they can reach it easily and comfortably. This quaint illustration has often recurred to me in the study, and made me anxiously consider whether I was putting the truth in such a way that the congregation could grasp it.