Imagination is “the power or faculty of the mind by which it perceives and forms ideas of things communicated to it by the organs of sense.” Webster. It is by this faculty that ideal images, or pictures of absent objects and scenes are formed. For instance, when in the silence of the night, reviewing the events of the day, we see the persons that we have visited, the country through which we have passed, and other things which have struck our vision, it is the imagination that pictures these things in our minds.
Imagination was designed to represent real and true objects and scenes; but it sometimes goes farther than this: it creates things that are unreal and untrue. This is seen in Mythology, where we read the description of creatures and scenes which have existed only in the imagination. This is also seen in the description of the future state given by Mahomet; also in the doctrine of purgatory, and in many other fanciful doctrines which are the fruit of unsanctified imaginations.
Imagination is naturally unruly, and is often used in picturing scenes that encourage the practice of sin, in magnifying the faults of others, and in manufacturing mountains of difficulties out of nothing. To illustrate we will suppose a case: A. and B. meet together. They have always been on good terms. A. moves along toward B. to pass compliments as on other occasions, but observes that B. is sad and rather backward in his remarks. These individuals part. A. looks back to the interview he has had with B. and calls up B. in his imagination, and says, How cold and sour he looked. How he stood off. How little he said. He never treated me so coldly. And the enemy comes in, and adds and adds to the picture, till B. looks ugly, independent and hard, and A. feels that he has been slighted and abused without a cause, and that B. has something against him. Soon A. and B. meet again. But this time B. comes up cheerfully, and A. stands off. Says B. What is the matter, Bro. A.? What is the matter, replies A.? You ought to know. You treated me coldly the other day without a just cause, and you have something against me. What makes you think so says B.? I know it is so, answers A. But B. replies, Why, dear Bro., I was examining my own heart and thinking about my imperfections, and since then I have got help, and I now feel free.
This is one case out of many in which we see the wrong use that is made of imagination. If A. had examined his own imperfections and checked his imagination, this trial might have been avoided. With many, an unsanctified imagination takes the lead, and the fruit is evil-surmisings, hatred, envy, lust, evil-speaking, unnecessary trials in families, in neighborhoods, and in the church of God, castles built in the air, fanaticism, etc.
But imagination may be very useful, and a source of much comfort. Would you derive real benefit and comfort from this faculty? Then employ it in picturing useful objects and scenes. Let it represent all that is lovely in the appearance and actions of others, and if you suffer it to represent the evil conduct of others, let it be only that you may help them, and more easily avoid the ways of sin. Let it form images of holy men and women spoken of in the Bible–especially of Jesus, the great example. Follow him from the manger to the cross. Behold him as he goes from place to place on his mission of love, suffering from weariness, hunger and thirst, from persecution and the temptations of Satan. Listen to the rich instructions that fall from his lips. See him weep over sinners. See him pray all night alone. Witness his agony in the garden, and the abuses that he receives as he is tried by his enemies. View him stretched between the heavens and the earth, with his hands and feet pierced, and the crown of thorns mutilating his sacred head. See the precious blood flow freely from his hands and feet. See it fall from his sacred head. Hear him pray for his enemies, and cry as he bears the sins of the whole world, “My God, my God, why hast thou forsaken me?” Follow him from earth to the heavenly sanctuary, where he pleads the merits of his blood in behalf of his people, and where his great mediatorial work will soon wind up preparatory to his coming to earth. Behold him coming in glory and majesty in the clouds of heaven, with all the holy angels. Witness the events connected with his coming. Picture in your minds the rich and glorious reward of the just, and the awful punishment of the unjust. And all these scenes will have a tendency to strengthen your faith, and encourage you to love the Lord, and imitate his virtues, to shun the ways of sin, and walk in the path of holiness.
— D. T. Bourdeau, Sanctification, pp. 26-29