No glimpse is wasted, even if it does pass away. For not only does it leave a memory to stir comfort guide inspire or meditate upon, but it also leaves a positive advance forward. Each glimpse is to be regarded as a step taken in the direction of the goal, or as a stage in the process of work needed to be done on oneself, or as a further cleansing of the accretions impurities animalities and egoisms which hide the true Self. If his own work is fully and faithfully done, the time comes when the power to prolong a glimpse is at the disciple's command. He is then able not only to bring it on at will but also to extend its length at will.
-- Notebooks Category 22: Inspiration and the Overself > Chapter 8: Glimpses and Permanent Illumination > # 72