Mother Teresa was in the Dark Night for fifty years or so. One must understand this is a necessary step to perfection.
St. John of the Cross describes the Dark Night of the Soul better than most saints and invented the term. In the next few days, I shall cover some, not all, of his points. If I could distil his wisdom in a few words, it would be these points.
One, consolations are either completely absence or rare at this stage of purification.
Two, one rests in suffering rather than resting in consolation.
Three, God is Present, but veiled, as in the Eucharist. He surrounds the person with love, but a love which cannot be grasped or understood in any human terms. He is totally Other.
Four, a person cannot rush through this stage. In fact, for many saints, it is very long.
Five, the two keys words are aridity and abandonment. But, one is at peace in both.
2. This is the first and principal benefit caused by this arid and dark night of contemplation: the knowledge of oneself and of one’s misery. For, besides the fact that all the favours which God grants to the soul are habitually granted to them enwrapped in this knowledge, these aridities and this emptiness of the faculties, compared with the abundance which the soul experienced aforetime and the difficulty which it finds in good works, make it recognize its own lowliness and misery, which in the time of its prosperity it was unable to see. Of this there is a good illustration in the Book of Exodus, where God, wishing to humble the children of Israel and desiring that they should know themselves, commanded them to take away and strip off the festal garments and adornments wherewith they were accustomed to adorn themselves in the Wilderness, saying: ‘Now from henceforth strip yourselves of festal ornaments and put on everyday working dress, that ye may know what treatment ye deserve.’81 This is as though He had said: Inasmuch as the attire that ye wear, being proper to festival and rejoicing, causes you to feel less humble concerning yourselves than ye should, put off from you this attire, in order that henceforth, seeing yourselves clothed with vileness, ye may know that ye merit no more, and may know who ye are. Wherefore the soul knows the truth that it knew not at first, concerning its own misery; for, at the time when it was clad as for a festival and found in God much pleasure, consolation and support, it was somewhat more satisfied and contented, since it thought itself to some extent to be serving God. It is true that such souls may not have this idea explicitly in their minds; but some suggestion of it at least is implanted in them by the satisfaction which they find in their pleasant experiences. But, now that the soul has put on its other and working attire—that of aridity and abandonment—and now that its first lights have turned into darkness, it possesses these lights more truly in this virtue of self-knowledge, which is so excellent and so necessary, considering itself now as nothing and experiencing no satisfaction in itself; for it sees that it does nothing of itself neither can do anything. And the smallness of this self-satisfaction, together with the soul’s affliction at not serving God, is considered and esteemed by God as greater than all the consolations which the soul formerly experienced and the works which it wrought, however great they were, inasmuch as they were the occasion of many imperfections and ignorances. And from this attire of aridity proceed, as from their fount and source of self-knowledge, not only the things which we have described already, but also the benefits which we shall now describe and many more which will have to be omitted.
All sourcing will be from here.
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