“The Expulsive Power of a New Affection”
Thomas Chalmers, a Scottish minister from the 19th century, wrote about this need powerfully in his sermon, “The Expulsive Power of a New Affection.” In the sermon, Chalmers writes about how most people’s desires change over time. Normally, a person moves from childish appetites to physical pleasure, from pleasure to the love of money, from the love of money to a lust for power.
There is not one of these transformations in which the heart is left without an object. Its desire for one particular object may be conquered; but as to its desire for having some one object or other, this is unconquerable. . . . Such is the grasping tendency of the human heart, that it must have a something to lay hold of . . . [This means] 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 . . . 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.
You can read the rest of Chalmers’ sermon here.