‘God is love’, and he who seeks to establish its bounds is like a blind man attempting to count the grains of sand in the deeps of the sea. In quality, love is the likeness of God, as far as this is possible to mortals; in action, it is intoxication of the soul; in its properties, it is the source of faith, the abyss of long-suffering, the sea of humility. Love is real renunciation of every contrary thought, for it ‘thinketh no evil’ (I Cor. 13:5). Love, passionlessness and sonship differ only in name. As light, fire and flame are combined in one single action, so it is with these three.
-Monks Callistus and Ignatius, Directions to Hesychasts no. 90, “Writings from the Philokalia on Prayer of the Heart”; Faber and Faber pg. 257