Picked this up from Challies.com. The quotes is from Jonathan Edward‘s The Religious Affection:
The more a true saint loves God with a gracious love, the more he desires to love him, and the more uneasy is he at his want of love to him; the more he hates sin, the more he desires to hate it, and laments that he has so much remaining love to it; the more he mourns for sin, the more he longs to mourn for sin; the more his heart is broke, the more he desires it should be broke the more he thirsts and longs after God and holiness, the more he longs to long, and breathe out his very soul in longings after God: the kindling and raising of gracious affections is like kindling a flame; the higher it is raised, the more ardent it is; and the more it burns, the more vehemently does it tend and seek to burn.…Spiritual good is of a satisfying nature; and for that very reason, the soul that tastes, and knows its nature, will thirst after it, and a fullness of it, that it may be satisfied. And the more he experiences, and the more he knows this excellent, unparalleled, exquisite, and satisfying sweetness, the more earnestly will he hunger and thirst for more, until he comes to perfection. And therefore this is the nature of spiritual affections, that the greater they be, the greater the appetite and longing is, after grace and holiness.
I started to read The Religious Affection today. I figured I picked up a good classic.