Often, people misuse that term for the difficulty Christians face, the struggles they go through, to reach knowledge, or faith, or rest in Christ. Actually, it's what seems like spiritual coma or death through which the soul passes through on the "purgative way," while it is detached from all comfort and light in prayer, from satisfaction, spiritual pride and avarice, to find union with Jesus Christ on earth and in Heaven.
I flipped open my laptop to write an appeal about my own spiritual coldness and dryness and found Roz' post and KBob's link - thank you, brother and sister. But mine is not the purification of Juan de la Cruz' dark night. It's plain old ordinary fallenness: clinging on to habitual sinfulness, laziness in devotion. I can't weaken Christ's love for me, but I can sure get the heck out of the way of His Grace by turning away towards decidedly lesser goods, abandoning the greatest Good. I can also fool myself that because I'm pretty dependable about giving time and money and attention to the church, that I can pick up enough Face Time Points to cruise along until I get around to embracing humility and single-footing it on the Narrow Way.
St. John, like all saints, never goes out of date or relevance. He says something wonderful in the link in Chapter II (no way to point to it directly):
5. Some of these beginners, too, make little of their faults, and at other times become over-sad when they see themselves fall into them, thinking themselves to have been saints already; and thus they become angry and impatient with themselves, which is another imperfection. Often they beseech God, with great yearnings, that He will take from them their imperfections and faults, but they do this that they may find themselves at peace, and may not be troubled by them, rather than for God's sake; not realizing that, if He should take their imperfections from them, they would probably become prouder and more presumptuous still. They dislike praising others and love to be praised themselves; sometimes they seek out such praise. Herein they are like the foolish virgins, who, when their lamps could not be lit, sought oil from others. (emphasis mine)
Well, howdy Therese! I want God to take away my sinfulness so I can be pleased with myself and my holiness! Bow down before the Idol Comfort! I don't want to push sinfulness away from myself, solely with the help of His Grace, to follow more closely God's Will. St. Paul says it clearly, too, in 2Cor12:7 and following:
Because of the surpassing greatness of the revelations, for this reason, to keep me from exalting myself, there was given me a thorn in the flesh, a messenger of Satan to torment me -- to keep me from exalting myself. Concerning this I implored the Lord three times that it might leave me.
We don't know what it was that tormented him - I see some commenters refer to sinfulness and others to poor eyesight ("see with what large letters I write to you!").
The lesson I've learned today, again, again, is that (1) Only His Grace is necessary for any good, for any turning towards the Lord, (2) I'm no better than anyone else, gol dang it, (3) I'm a sinner, (4) Tomorrow's another day, to rise again and carry my cross.
What do you do to kick yourself in the spiritual heinie when you've become lukewarm?