Below is an excerpt from, "The Soul of Kierkegaard: Selections from His Journals." Edited by Alexander Dru. Dover Publications, Inc: Mineola, New York. 2003. Pg. 104.
It is really curious how men, whom I otherwise look upon as honest, and who in other respects are not my enemies, lie monstrously, and are hardly conscious of it themselves, when they really get into a passion. Passion has an extraordinary power. How foolish, then, is the modern seeking after system upon system, as though help was to be found there; no, passion must be purified. At the present time I am incidentally experiencing expressions of it.