and want obstinately to keep what is good for ourselves, we must even in urgent cases of this sort speak the truth, and so become guilty of the death of another: but if we prefer what is for another’s advantage to our own good, and satisfy the demands of the Apostle, we shall certainly have to put up with the necessity of lying. And therefore we shall not be able to keep a perfect heart of love, or to seek, as Apostolic perfection requires, the things of others, unless we relax a little in those things which concern the strictness and perfection of our own lives, and choose to condescend with ready affection to what is useful to others, and so with the Apostle become weak to the weak, that we may be able to gain the weak.
Complete source paragraph · Conferences of John Cassian, Part II, Chapter XIX.; original source section: Chapter 19; original book/conference: XVII. The Second Conference of Abbot Joseph., source paragraph 4 · Original source