A Christian has great difficulty in attaining three things: grief (over sins), tears, and the continual memory of death. Yet these contain all of the other virtues.
According to the degree to which the intellect is stripped of the passions, the Holy Spirit initiates the intellect into the mysteries of the age to be.
Do not neglect the practice of the virtues; if you do, your spiritual knowledge will decrease, and when famine occurs you will go down into Egypt (Genesis 41:57, 46:6).