The fourth considers the paradoxical state of Canticles 5:2, “I sleep, but my heart wakes.”

First, Sibbes notes the concept of the heart as used in the Scripture:

The word heart, you know, includes the whole soul, for the understanding is the heart, ‘an understanding heart,’ Job 38:36. To ‘lay things up in our hearts,’ Luke 2:51, there it is memory; and to cleave in heart is to cleave in will, Acts 11:23. To ‘rejoice in heart,’ Isa. 30:29, that is in the affection. So that all the powers of the soul, the inward man, as Paul calleth it, 2 Cor. 4:16, is the heart.

By the terms “waking” and “sleeping”, Sibbes takes it for the state of the heart in a Christian, which is both redeemed and yet corruption remains. This makes for Sibbes’ first observation on the text:

Obs.1. You see here, then, first of all, in this correction, that a Christian hath two principles in him, that which is good, and that which is evil, whence issueth the weakness of his actions and affections. They are all mixed, as are the principles from which they come forth.

The second observation is by means of the Spirit the has knowledge of himself:

We may observe, further, that a Christian man may know how it is with himself. Though he be mixed of flesh and spirit, he hath a distinguishing knowledge and judgment whereby he knows both the good and evil in himself.

He compares the human heart in its nature as being like a lightless dungeon, but the Spirit is a light that searches the dark corners of the heart.He also notes that the in times of temptation, the work of the Spirit may be hindered in the human heart such a man not righty know himself:

In a dungeon where is nothing but darkness, both on the eye that should see and on that which should be seen, he can see nothing; but where there is a supernatural principle, where there is this mixture, there the light of the Spirit searcheth the dark corners of the heart. A man that hath the Spirit knoweth both; he knoweth himself and his own heart. The Spirit hath a light of its own, even as reason hath. How doth reason know what it doth? By a reflect act inbred in the soul. Shall a man that is natural reflect upon his state, and know what he knows, what he thinks, what he doth, and may not the soul that is raised to an higher estate know as much? Undoubtedly it may. Besides, we have the Spirit of God, which is light, and self-evidencing. It shews unto us where it is, and what it is. The work of the Spirit may sometimes be hindered, as in times of temptation. Then I confess a man may look wholly upon corruption, and so mistake himself in judging by that which he sees present in himself, and not by the other principle which is concealed for a time from him. But a Christian, when he is not in such a temptation, he knows his own estate, and can distinguish between the principles in him of the flesh and spirit, grace and nature.

Third, Sibbes notes that we should acknowledge both good work of the Spirit in our heart as well as our indwelling corruption. But,

Many help Satan, the accuser, and plead his cause against the Spirit, their comforter, in refusing to see what God seeth in them. We must make conscience of this, to know the good as well as the evil, though it be never so little.

Note that it is the job of Satan to accuse the believer. His goal is not to bring the conscience to a state of repentance, but to crush the heart in despair. There is a worldly sorrow and a sorrow of repentance.

This is a theme which Sibbes develops in other places. He works out the fact that a believer may be discouraged and overcome with sin and yet still not be destroyed as a believer. First, the Christian still has a principle of judgment. Even in the worst state, the Christian retains the capacity to know the moral truth of his actions.

Moreover, the will when focused can still choose the better part.

Take David in his sleepy time between his repentance and his foul sin. If one should have asked him what he thought of the ways of God and of the contrary, he would have given you an answer out of sound judgment thus and thus. If you should have asked him what course he would have followed in his choice, resolution, and purpose, he would have answered savourly.

Third, the affections of the believer will ultimately return to Christ:

Again, there remaineth affection answerable to their judgment, which, though they find, and feel it not for a time, it being perhaps scattered, yet there is a secret love to Christ, and to his cause and side, joined with joy in the welfare of the church and people of God; rejoicing in the prosperity of the righteous, with a secret grief for the contrary. The pulses will beat this way, and good affections will discover themselves. Take him in his sleepy estate, the judgment is sound in the main, the will, the affections, the joy, the delight, the sorrow. This is an evidence his heart is awake.

Fourth, the conscience, even when the believer has fallen into sin will respond. Sibbes gives of David when confronted by Nathan:

The conscience likewise is awake. The heart is taken ofttimes for the conscience in Scripture. A good conscience, called a merry heart, is ‘a continual feast,’ Prov. 15:15. Now, the conscience of God’s children is never so sleepy but it awaketh in some comfortable measure. Though perhaps it may be deaded*in a particular act, yet notwithstanding there is so much life in it, as upon speech or conference, &c., there will be an opening of it, and a yielding at the length to the strength of spiritual reason. His conscience is not seared. David was but a little roused by Nathan, yet you see how he presently confessed ingeniously^†that he had sinned, 2 Sam. 12:13. So, when he had numbered the people, his conscience presently smote him, 2 Sam. 24:10; and when he resolved to kill Nabal and all his family, which was a wicked and carnal passion, in which there was nothing but flesh; yet when he was stopped by the advice and discreet counsel of Abigail, we see how presently he yielded, 1 Sam. 25:32, seq.There is a kind of perpetual tenderness of conscience in God’s people. All the difference is of more or less.

And finally, obedience to God will ultimately return; even when there has been a fall. Sibbes aptly distinguishes between “a state and a fit”. A state would be the general basic estate and a “fit” would be an illness:

And answerable to these inward powers is the outward obedience of God’s children. In their sleepy estate they go on in a course of obedience. Though deadly and coldly, and not with that glory that may give others good example or yield themselves comfort, yet there is a course of good duties. His ordinary way is good, howsoever he may step aside. His fits may be sleepy when his estate is waking. We must distinguish between a state and a fit. A man may have an aguish fit in a sound body. The state of a Christian is a waking state in the inward man. The bye-courses he falleth into are but fits, out of which he recovers himself.