Every athlete knows that for each great training session there is a backlash, usually a day or two of deep physical soreness and mental fatigue, which sets in a day or two after the session. The spirit has overstretched body and mind, damaging both, necessitating a few days recovery, after which both will be all the stronger for it. This is the rationale behind any serious practice, and all good students learn to recognise the difference between genuine training fatigue and the inevitable reluctance to train. And it is exactly the same with spiritual work: fall deeply into meditation or prayer and you'll emerge feeling transported and transformed, but expect to pay a price when that feeling wears off.