Expounds the fourth line  and describes the wondrous hiding place wherein the soul is set during this night. Shows how, although the devil has an entrance into other places that are very high, he has none into this.
IN concealment’ is as much as to say in a hiding-place,’ or in hiding’; and thus, what the soul here says (namely, that it went forth in darkness and in concealment’) is a more complete explanation of the great security which it describes itself in the first line of the stanza as possessing, by means of this dark contemplation upon the road of the union of the love of God.
2. When the soul, then, says in darkness and in concealment,’ it means that, inasmuch as it journeyed in darkness after the manner aforementioned, it went in hiding and in concealment from the devil and from his wiles and stratagems. The reason why, as it journeys in the darkness of this contemplation, the soul is free, and is hidden from the stratagems of the devil, is that the infused contemplation which it here possesses is infused into it passively and secretly, without the knowledge of the senses and faculties, whether interior or exterior, of the sensual part. And hence it follows that, not only does it journey in hiding, and is free from the impediment which these faculties can set in its way because of its natural weakness, but likewise from the devil; who, except through these faculties of the sensual part, cannot reach or know that which is in the soul, nor that which is taking place within it. Wherefore, the more spiritual, the more interior and the more remote from the senses is the communication, the farther does the devil fall short of understanding it.
3. And thus it is of great importance for the security of the soul that its inward communication with God should be of such a kind that its very senses of the lower part will remain in darkness  and be without knowledge of it, and attain not to it: first, so that it may be possible for the spiritual communication to be more abundant, and that the weakness of its sensual part may not hinder the liberty of its spirit; secondly because, as we say, the soul journeys more securely since the devil cannot penetrate so far. In this way we may understand that passage where Our Saviour, speaking in a spiritual sense, says: Let not thy left hand know what thy right hand doeth.’  Which is as though He had said: Let not thy left hand know that which takes place upon thy right hand, which is the higher and spiritual part of the soul; that is, let it be of such a kind that the lower portion of thy soul, which is the sensual part, may not attain to it; let it be a secret between the spirit and God alone.
4. It is quite true that oftentimes, when these very intimate and secret spiritual communications are present and take place in the soul, although the devil cannot get to know of what kind and manner they are, yet the great repose and silence which some of them cause in the senses and the faculties of the sensual part make it clear to him that they are taking place and that the soul is receiving a certain blessing from them. And then, as he sees that he cannot succeed in thwarting them in the depth of the soul, he does what he can to disturb and disquiet the sensual part–that part to which he is able to attain–now by means of afflictions, now by terrors and fears, with intent to disquiet and disturb the higher and spiritual part of the soul by this means, with respect to that blessing which it then receives and enjoys. But often, when the communication of such contemplation makes its naked assault upon the soul and exerts its strength upon it, the devil, with all his diligence, is unable to disturb it; rather the soul receives a new and a greater advantage and a securer peace. For, when it feels the disturbing presence of the enemy, then–wondrous thing!–without knowing how it comes to pass, and without any efforts of its own, it enters farther into its own interior depths, feeling that it is indeed being set in a sure refuge, where it perceives itself to be most completely withdrawn and hidden from the enemy. And thus its peace and joy, which the devil is attempting to take from it, are increased; and all the fear that assails it remains without; and it becomes clearly and exultingly conscious of its secure enjoyment of that quiet peace and sweetness of the hidden Spouse, which neither the world nor the devil can give it or take from it. In that state, therefore, it realizes the truth of the words of the Bride about this, in the Songs, namely: ‘see how threescore strong men surround the bed of Solomon, etc., because of the fears of the night.’  It is conscious of this strength and peace, although it is often equally conscious that its flesh and bones are being tormented from without.
5. At other times, when the spiritual communication is not made in any great measure to the spirit, but the senses have a part therein, the devil more easily succeeds in disturbing the spirit and raising a tumult within it, by means of the senses, with these terrors. Great are the torment and the affliction which are then caused in the spirit; at times they exceed all that can be expressed. For, when there is a naked contact of spirit with spirit, the horror is intolerable which the evil spirit causes in the good spirit (I mean, in the soul), when its tumult reaches it. This is expressed likewise by the Bride in the Songs, when she says that it has happened thus to her at a time when she wished to descend to interior recollection in order to have fruition of these blessings. She says: I went down into the garden of nuts to see the apples of the valleys, and if the vine had flourished. I knew not; my soul troubled me because of the chariots’–that is, because of the chariots and the noise of Aminadab, which is the devil. 
6. At other times it comes to pass that the devil is occasionally able to see certain favours which God is pleased to grant the soul when they are bestowed upon it by the mediation of a good angel; for of those favours which come through a good angel God habitually allows the enemy to have knowledge: partly so that he may do that which he can against them according to the measure of justice, and that thus he may not be able to allege with truth that no opportunity is given him for conquering the soul, as he said concerning Job.  This would be the case if God allowed not a certain equality between the two warriors–namely, the good angel and the bad–when they strive for the soul, so that the victory of either may be of the greater worth, and the soul that is victorious and faithful in temptation may be the more abundantly rewarded.
7. We must observe, therefore, that it is for this reason that, in proportion as God is guiding the soul and communing with it, He gives the devil leave to act with it after this manner. When the soul has genuine visions by the instrumentality of the good angel (for it is by this instrumentality that they habitually come, even though Christ reveal Himself, for He scarcely ever appears  in His actual person), God also gives the wicked angel leave to present to the soul false visions of this very type in such a way that the soul which is not cautious may easily be deceived by their outward appearance, as many souls have been. Of this there is a figure in Exodus,  where it is said that all the genuine signs that Moses wrought were wrought likewise in appearance by the magicians of Pharaoh. If he brought forth frogs, they brought them forth likewise; if he turned water into blood, they did the same.
8. And not only does the evil one imitate God in this type of bodily vision, but he also imitates and interferes in spiritual communications which come through the instrumentality of an angel, when he succeeds in seeing them, as we say (for, as Job said  : Omne sublime videt). These, however, as they are without form and figure (for it is the nature of spirit to have no such thing), he cannot imitate and counterfeit like those others which are presented under some species or figure. And thus, in order to attack the soul, in the same way as that wherein it is being visited, his fearful spirit presents a similar vision in order to attack and destroy spiritual things by spiritual. When this comes to pass just as the good angel is about to communicate spiritual contemplation to the soul, it is impossible for the soul to shelter itself in the secrecy and hiding-place of contemplation with sufficient rapidity not to be observed by the devil; and thus he appears to it and produces a certain horror and perturbation of spirit which at times is most distressing to the soul. Sometimes the soul can speedily free itself from him, so that there is no opportunity for the aforementioned horror of the evil spirit to make an impression on it; and it becomes recollected within itself, being favoured, to this end, by the effectual spiritual grace that the good angel then communicates to it.
9. At other times the devil prevails and encompasses the soul with a perturbation and horror which is a greater affliction to it than any torment in this life could be. For, as this horrible communication passes direct from spirit to spirit, in something like nakedness and clearly distinguished from all that is corporeal, it is grievous beyond what every sense can feel; and this lasts in the spirit for some time, yet not for long, for otherwise the spirit would be driven forth from the flesh by the vehement communication of the other spirit. Afterwards there remains to it the memory thereof, which is sufficient to cause it great affliction.
10. All that we have here described comes to pass in the soul passively, without its doing or undoing anything of itself with respect to it. But in this connection it must be known that, when the good angel permits the devil to gain this advantage of assailing the soul with this spiritual horror, he does it to purify the soul and to prepare it by means of this spiritual vigil for some great spiritual favour and festival which he desires to grant it, for he never mortifies save to give life, nor humbles save to exalt, which comes to pass shortly afterwards. Then, according as was the dark and horrible purgation which the soul suffered, so is the fruition now granted it of a wondrous and delectable spiritual contemplation, sometimes so lofty that there is no language to describe it. But the spirit has been greatly refined by the preceding horror of the evil spirit, in order that it may be able to receive this blessing; for these spiritual visions belong to the next life rather than to this, and when one of them is seen this is a preparation for the next.
11. This is to be understood with respect to occasions when God visits the soul by the instrumentality of a good angel, wherein, as has been said, the soul is not so totally in darkness and in concealment that the enemy cannot come within reach of it. But, when God Himself visits it, then the words of this line are indeed fulfilled, and it is in total darkness and in concealment from the enemy that the soul receives these spiritual favours of God. The reason for this is that, as His Majesty dwells substantially in the soul, where neither angel nor devil can attain to an understanding of that which comes to pass, they cannot know the intimate and secret communications which take place there between the soul and God. These communications, since the Lord Himself works them, are wholly Divine and sovereign, for they are all substantial touches of Divine union between the soul and God; in one of which the soul receives a greater blessing than in all the rest, since this is the loftiest degree  of prayer in existence.
12. For these are the touches that the Bride entreated of Him in the Songs, saying: Osculetur me osculo oris sui.  Since this is a thing which takes place in such close intimacy with God, whereto the soul desires with such yearnings to attain, it esteems and longs for a touch of this Divinity more than all the other favours that God grants it. Wherefore, after many such favours have been granted to the Bride in the said Songs, of which she has sung therein, she is not satisfied, but entreats Him for these Divine touches, saying: ‘ Who shall give Thee to me, my brother, that I might find Thee alone without, sucking the breasts of my mother, so that I might kiss Thee with the mouth of my soul, and that thus no man should despise me or make bold to attack me.’  By this she denotes the communication which God Himself alone makes to her, as we are saying, far from all the creatures and without their knowledge, for this is meant by alone and without, sucking, etc.’–that is, drying up and draining the breasts of the desires and affections of the sensual part of the soul. This takes place when the soul, in intimate peace and delight, has fruition of these blessings, with liberty of spirit, and without the sensual part being able to hinder it, or the devil to thwart it by means thereof. And then the devil would not make bold to attack it, for he would not reach it, neither could he attain to an understanding of these Divine touches in the substance of the soul in the loving substance of God.
13. To this blessing none attains save through intimate purgation and detachment and spiritual concealment from all that is creature; it comes to pass in the darkness, as we have already explained at length and as we say with respect to this line. The soul is in concealment and in hiding, in the which hiding-place, as we have now said, it continues to be strengthened in union with God through love, wherefore it sings this in the same phrase, saying: In darkness and in concealment.’
14. When it comes to pass that those favours are granted to the soul in concealment (that is, as we have said, in spirit only), the soul is wont, during some of them, and without knowing how this comes to pass, to see itself so far withdrawn and separated according to the higher and spiritual part, from the sensual and lower portion, that it recognizes in itself two parts so distinct from each other that it believes that the one has naught to do with the other, but that the one is very remote and far withdrawn from the other. And in reality, in a certain way, this is so; for the operation is now wholly spiritual, and the soul receives no communication in its sensual part. In this way the soul gradually becomes wholly spiritual; and in this hiding-place of unitive contemplation its spiritual desires and passions are to a great degree removed and purged away. And thus, speaking of its higher part, the soul then says in this last line:
My house being now at rest. 
 i.e., in the original Spanish and in our verse rendering of the poem in The Complete Works of St. John of the Cross, Ed. by E. Allison Peers, Vol. II (The Newman Press, Westminster, Md.).
 [The Spanish also admits of the rendering: remain shut off from it by darkness.’]
 Matthew vi, 3.
 Canticles iii, 7-8.
 Canticles vi, 10 [A.V., vi, 11-12].
 Job i, 1-11.
 Such is the unanimous opinion of theologians. Some, with St. Thomas (Pt. III, q. 57, a. 6), suppose that the appearance which converted St. Paul near Damascus was that of Our Lord Jesus Christ in person.
 Exodus vii, 11-22; viii, 7.
 Job xli, 25.
 [Lit., ‘step.’ Cf. Bk. II, chap. xix, first note, above.]
 Canticles i, 1.
 Canticles viii, 1.
 The word translated at rest’ is a past participle: more literally, ‘stilled.’