Everything, absolutely everything in religion is ambiguous, and this ambiguity can be cleared only by humility, so that the whole spiritual life is or must be directed at seeking humility. The signs of humility: joy! Pride excludes joy. Then: simplicity, i.e., the absence of any turn into one’s self. Finally, trust, as the main directive in life, applied to everything (purity of heart, when man can see God). The signs of pride are: the absence of joy; complexity and fear.
(Fr. Alexander Schmemann, The Journals of Fr. Alexander Schmemann, p. 161)