Having laid the foundations badly, they [covetous souls] are unworthy to raise an edifice of virtue and reach the summit of perfection. - John Cassian

Some faults grow up without any natural occasion giving birth to them, but simply from the free choice of a corrupt and evil will, as envy and this very sin of covetousness; which are caught (so to speak) from without, having no origination in us from natural instincts. But these, in proportion as they are easily guarded against and readily avoided, just so do they make wretched the mind that they have got hold of and seized, and hardly do they suffer it to get at the remedies which would cure it.

The holy person ... when, raised up from the earth, he contemplates all present and earthly realities as mere smoke and an empty shadow and disdains them as soon to disappear;
when, with ecstatic mind, he not only ardently desires future realities but even sees them with clarity;
when he is effectively fed by spiritual theoria;
when he sees unlocked to himself the heavenly sacraments in all their brightness;
when he sends prayers purely and swiftly to God;
and when, inflamed with spiritual ardor, he passes over to invisible and eternal realities with such utter eagerness of soul that he cannot bring himself to believe that he is in the flesh.

For the rest, Jesus is also seen by those who dwell in cities and towns and villages—that is, by those who have an active way of life and its obligations—but not with that brightness with which he appears to those who are able to climb with him the aforesaid mount of the virtues—namely, to Peter, James, and John. For it was in the desert that he appeared to Moses and spoke to Elijah.