Sufi

" … the only purpose of our life here on earth, if there be any, is the successful attainment of life's demands. It may seem strange at first sight that all which life demands should be allowable and worthwhile attaining; but on a closer study of life we see that the demands of our external self are the only ones we know, and we are ignorant of the demands of the true self, our inner life. For instance, we know that we want good food and nice clothes, comfort of living and every convenience for moving about; honor, possessions, and all necessary means for the satisfaction of our vanity, all of which for the moment appear to us as our life's only demands; but neither they nor their joy remain with us constantly. We then come to think that what we had was but a little and that perhaps more would satisfy us, and still more would suffice our need; but this is not so. Even if the whole universe were within our grasp it would be impossible fully to satisfy our life's demands. This shows that our true life has quite different demands from those with which we are familiar."
@ wahiduddin.net

"The essential questions of man's being add another dimension to human suffering. They do not allow us to feel satisfied even when this or that goal has been fulfilled. When one attains the goal he strives for, he immediately feels he's missing yet another pleasure. This prevents him from enjoying his achievements, and his suffering is renewed. In retrospect, he sees that he has spent most of his time making an effort to achieve his goals, and has gained very little pleasure from the successes themselves.
Kabbalah

"He who seeks nourishment that does not nourish reels from desire to gratification and in gratification craves desire. Mad pursuit of pleasure for the satisfaction of the senses never brings one to the goal. One should never … follow this path, for nothing good can come of it."
I Ching #27 Line 3

"Greed is a bottomless pit which exhausts the person in an endless effort to satisfy the need without ever reaching satisfaction."
Erich Fromm - Escape from Freedom.

"All things are derived from One great Principle, and this Principle is the unknown and invisible God. From Him a substantial power immediately proceeds, which is the image of God, and the source of all subsequent emanations. Matter is nothing more than the most remote effect of the emanative energy of the Deity."
—Kabbalah, quoted in Isis Unveiled, vol. 2