from Thomas Chalmers, "The Expulsive Power of a New Affection":
The love of the world cannot be expunged by a mere demonstration of the world's worthlessness. But may it not be supplanted by the love of that which is more worthy than itself? The heart cannot be prevailed upon to part with the world, by a simple act of resignation. But may not the heart be prevailed upon to admit into its preference another, who shall subordinate the world, and bring it down from its wonted ascendancy?
If the throne which is placed there must have an occupier, and the tyrant that now reigns has occupied it wrongfully, he may not leave a bosom which would rather detain him than be left in desolation. But may he not give way to the lawful sovereign, appearing with every charm that can secure His willing admittance, and taking unto himself His great power to subdue the moral nature of man, and to reign over it?
In a word, if the way to disengage the heart from the positive love of one great and ascendant object, is to fasten it in positive love to another, then it is not by exposing the worthlessness of the former, but by addressing to the mental eye the worth and excellence of the latter, that all old things are to be done away and all things are to become new. To obliterate all our present affections by simply expunging them, and so as to leave the seat of them unoccupied, would be to destroy the old character, and to substitute no new character in its place. But when they take their departure upon the ingress of other visitors; when they resign their sway to the power and the predominance of new affections; when, abandoning the heart to solitude, they merely give place to a successor who turns it into as busy a residence of desire and interest and expectation as before - there is nothing in all this to thwart or to overbear any of the laws of our sentient nature - and we see how, in fullest accordance with the mechanism of the heart, a great moral revolution may be made to take place upon it.
This, we trust, will explain the operation of that charm which accompanies the effectual preaching of the gospel.