The ruling passion

(William Sprague, "Lectures to Young People")

"We too all previously lived among them in our fleshly desires,
 carrying out the inclinations of our flesh and thoughts, and by
 nature we were children under wrath, as the others were also."
     Ephesians 2:3

In the time of youth, there is a natural relish for worldly pleasure.
Previous to conversion, no doubt the love of pleasure is the ruling
passion. There is a natural buoyancy of spirits incident to that
period, which usually finds its element, either in scenes of mirthful
diversion, or sensual indulgence.

But whenever the heart comes under the influence of true piety,
it, of course, yields to the dominion of a new set of principles;
and he who was before supremely a lover of pleasure--now
becomes supremely a lover of God.

"For those whose lives are according to the flesh think about
 the things of the flesh; but those whose lives are according
 to the Spirit, about the things of the Spirit." Romans 8:5