According to the teachings of the Holy Fathers, in order to destroy insensibility man needs a constant, patient, uninterrupted activity against insensibility; he needs a constant, pious, and attentive life.
Prayer offered up at night possesses a great power, more so than the prayer of the day-time. Therefore all the righteous prayed during the night, while combating the heaviness of the body and the sweetness of sleep and repelling bodily nature.