Psalm 44 - We are Reckoned as Sheep for Slaughter
On "giving understanding" see Psalm 32.
What understanding does this Psalm give us?:
1. That victory or revival is not from us but from faith in God. (vv 3-7; Rom 8:37))
2. God searches the hearts (v21; Rom 8:27)
3. That our suffering can be for God's sake and not due to our failure or sin. (v22; Rom 8:17,36)

Romans 8 expounds this Psalm giving us further understanding:
As God's people, we will suffer for His sake (Rom 8:17).
Passing  through these sufferings faithful to Christ qualifies us to be fellow heirs of God with Christ and to be glorified together.
God causes all things, including these sufferings to work together for our good who love Him and are called according to His purpose. (Rom 8:28)
We should not fear these sufferings because those cannot separate us from the love of Christ (Rom 8:35-39).

This psalm was written during or after the Babylonian captivity according to v11. Since it is not longing for return from captivity, I place it in the time of Ezra 4 during the troublous times of rebuilding the temple when the building was stopped.

By Christians [this Psalm] can best be understood if put into the mouth of the church when persecution is peculiarly severe. - Charles H. Spurgeon

Structure of Psalm:
1. God's help to Israel in times past vv1-3
2. Prayer for God to help us as in former days vv4-8
3. The current state of non-help from God vv9-16
a. We are plundered by our enemies vv9-12
b. We are a reproach among the nations vv13-16
4. We have not forgotten You, God. vv17-22
5. Prayer for God to arise and help us. vv23-26
v1 "The expression, "heard with our ears, "may denote the pleasure with which they listened, the intensity of their interest, the personality of their hearing, and the lively remembrance they had of the romantic and soul stirring narrative. Too many have ears but hear not; happy are they who, having ears, have learned to hear. " - Spurgeon

"It is to be feared that many children of [Christians] could plead very little before God of what their fathers have told them. When fathers are tongue tied religiously with their offspring, need they wonder if their children's hearts remain sin tied? Just as in all free nations men delight to gather around the hearth, and tell the deeds of valor of their sires "in the brave days of old, "so the people of God under the old dispensation made their families cheerful around the table, by rehearsing the wondrous doings of the Lord their God. Religious conversation need not be dull, and indeed it could not be if, as in this case, it dealt more with facts and less with opinions." - Spurgeon

"Note that the main point of the history transmitted from father to son was the work of God; this is the core of history, and therefore no man can write history aright who is a stranger to the Lord's work. It is delightful to see the footprints of the Lord on the sea of changing events, to behold him riding on the whirlwind of war, pestilence, and famine, and above all to see his unchanging care for his chosen people. Those who are taught to see God in history have learned a good lesson from their fathers, and no son of believing parents should be left in ignorance of so holy an art. A nation tutored as Israel was in a history so marvelous as their own, always had an available argument in pleading with God for aid in trouble, since he who never changes gives in every deed of grace a pledge of mercy yet to come. The traditions of our past experience are powerful pleas for present help. " - Spurgeon
v2 Lord, You did this in the past. Why not now?
v3. The enabler for the Lord to act on our behalf is not to credit the success to ourselves.

The Lord did it with 1) His right hand, 2) His arm 3) The light of His countenance
What the Lord does with His right hand is the main thing He is doing.
When the Lord does something with His arm, He does it with His strength.
The light of the Lord's countenance enables us to live before the Lord so that He delights in us.

Lord, why don't you delight in us now?

"The passage may be viewed as a beautiful parable of the work of salvation; men are not saved without prayer, repentance, etc., but none of those save a man, salvation is altogether of the Lord. Canaan was not conquered without the armies of Israel, but equally true is it that is was not conquered by them; the Lord was the conqueror, and the people were but instruments in his hands." - Spurgeon
v4 This begins a prayer. God, command deliverance for Jacob.

"Jacob's long life was crowded with trials and deliverances, and his descendants are here called by his name, as if to typify the similarity of their experience to that of their great forefather. He who would win the blessings of Israel must share the sorrows of Jacob. This verse contains a personal declaration and an intercessory prayer; those can pray best who make most sure of their personal interest in God, and those who have the fullest assurance that the Lord is their God should be the foremost to plead for the rest of the tried family of the faithful." - Spurgeon
v5 God, if you command deliverance for Jacob then this is what would happen.
To push down our enemies implies wrestling.

"Mark well that all the conquests of these believers are said to be "through Thee, ""through Thy name:" never let us forget this, lest going a warfare at our own charges, we fail most ignominiously. Let us not, however, fall into the equally dangerous sin of distrust, for the Lord can make the weakest of us equal to any emergency. Though today we are timid and defenseless as sheep, he can by his power make us strong as the firstling of his bullock. - Spurgeon
v6 This goes back to v3a. In order for God to bless us again, we need to not put confidence in ourselves nor our resources but in God.
I can't speak for the nation in this, so I speak for myself, I will not put confidence in my bow or sword. Revival begins with the individual (Rev 2:7; etc).
When God wants to accomplish something, He calls dedicated men and women to challenge His people and lead the way. - Warren W. Wiersbe
v7 This past glory is the opposite of the present situation as described in the following verses.
v8 God, In the past we boasted all the day in you. if You would command deliverance for Jacob, we would praise Your name forever, as our fathers did.
This is the only Selah in this psalm.
Pause to think about what was just said.

"Selah. A pause comes in fitly here, when we are about to descend from the highest to the lowest key. No longer are we to hear Miriam's timbrel, but rather Rachel's weeping. " - Spurgeon
v9 Lord this is our state. I lay it out before You.

"Alas! for a church and people when the Lord in the active energy of his Spirit withdraws from them, they want no greater shame or sorrow. He will not cast away his people finally and totally, but many a church has been left to defeat and disgrace on account of sin, and therefore all churches should be exceedingly watchful lest the like should happen to themselves. Poverty and distress bring no shame on a people, but the Lord's absence takes from a church everything which can exalt and ennoble. ...
Vain are the combined efforts of the most zealous workers if God's arm be not revealed. May none of us in our churches have to mourn over the ministry, the Sabbath school, the missionary work, the visiting, the street preaching, left to be carried out without the divine aid. If our great ally will not go with us our defeat is inevitable. " - Spurgeon
v10 In times past (v7) You put them to shame that hate us. Now they spoil us with impunity.

"In spiritual experience we know what it is to be despoiled by our enemies; doubts and fears rob us of our comforts, and terrible forebodings spoil us of our hopes; and all because the Lord, for wise purposes, sees fit to leave us to ourselves. Alas! for the deserted soul; no calamity can equal the sorrow of being left of God, though it be but for a small moment. " - Spurgeon
v11 "All this is ascribed to the Lord, as being allowed by him, and even appointed by his decree. It is well to trace the hand of God in our sorrows, for it is surely there. " - Spurgeon

There are times when murdering a Jew is considered no more evil than slaughtering a sheep, and we are forced to scatter and seek new havens - Rabbi Hirsch
v12 Lord, what good does our suffering do for You? Appeal to God's self interest in our prayer.
v13 "[The psalmist] used the very best of arguments, for the sufferings of his chosen touch the heart of God far more readily than any other reasonings. Blessed be his name, our great Advocate above knows how to avail himself of this powerful plea, and if we are at this hour enduring reproach for truth's sake, he will urge it before the eternal throne;" - Spurgeon
v14 "Those whose heads were emptiest wagged them at the separated people. They were the common butts of every fool's arrow. Such has been the lot of the righteous in ages past, such is their portion in a measure now, such may be yet again their heritage in the worst sense. The world knows not its nobility, it has no eye for true excellence: it found a cross for the Master, and cannot be expected to award crowns to his disciples. " - Spurgeon
v15 Why did the psalmist switch back to 1st person singular here? It is good to make "I" statements in our prayers, and not just "we" statements. The previous complaints in vv9 - 14 are facts. This verse is a feeling. It seems that the psalmist could not speak for the nation here, but spoke for himself.

He is a man of ill blood who is unconcerned for the sorrows of the church of which he is a member, or the nation of which he is a citizen; ...
It is well for a nation when there still exist in it men who lay to heart its sin and shame. God will have pity on his chastened ones, and it is a pledge thereof when he sends us choice ministers, men of tenderness, who make the people's case their own. - Spurgeon
v16 It seems that from mocking the people of God, the adversaries advanced to reviling God himself, they proceeded from persecution to the sin which is next of kin, namely blasphemy. - Spurgeon
v17 Israel did forget God and deal falsely with His covenant before the Babylonian captivity. The sons of Korah do not confess this in this psalm. Why was that not necessary? It may be that is necessary, but is not part of this psalm. This psalm doesn't contain everything necessary for prayer for revival.
I think he is talking about their current state of the remnant who came back from captivity for the sake of the Lord's testimony.
The sons of Korah here confess that what they sincerely believe is the case. In the church, we could say the same: Lord, we are keeping Your New Testament commandments. In speaking so, we are speaking for those who are being faithful to the Lord.

"When in the midst of many griefs we can still cling to God in loving obedience, it must be well with us. True fidelity can endure rough usage. Those who follow God for what they get, will leave him when persecution is stirred up, but not so the sincere believer; he will not forget his God, even though the worst come to the worst.  ...
This and the succeeding verses are suitable for the lips of martyrs, indeed the entire psalm might be called the martyr's complaint. Not for sin but for righteousness did the saints suffer, not for falsehood but for truth, not for forsaking the Lord, but for following hard after him. Sufferings of such a sort may be very terrible, but they are exceedingly honorable, and the comforts of the Lord shall sustain those who are accounted worthy to suffer for Christ's sake."  - Spurgeon
v18 "They were not absolutely perfect, but they were sincerely free from all wilful transgression. It was a healthy sign for the nation that her prophet poet could testify to her uprightness before God, both in heart and act; far oftener the case would have worn quite another color, for the tribes were all too apt to set up other gods and forsake the rock of their salvation. " - Spurgeon
v19 "To be true to a smiting God, even when the blows lay our joys in ruinous heaps, is to be such as the Lord delighteth in. Better to be broken by God than from God. Better to be in the place of dragons than of deceivers. ...
Better death than false of faith. Those who are true to God shall never find him false to them." - Spurgeon
v20 "This would be the first step in apostasy; men first forget the true, and then adore the false." - Spurgeon

Even under pain of death (v22), we did not render homage to other gods. - Stone Tanach
v21 "Would he not with holy indignation have detected unfaithfulness to itself, even had it been hidden in the heart and unrevealed in the life?
Not the heart only which is secret, but the secrets of the heart, which are secrets of the most secret thing, are as open to God as a book to a reader. The reasoning is that the Lord himself knew the people to be sincerely his followers, and therefore was not visiting them for sin; hence, then, affliction evidently came from quite another cause." - Spurgeon

God certainly knows this claim to be true. - Stone Tanach
v22 Quoted by Paul in Rom 8:36 to say that these sufferings will come upon us, but we don't need to fear them because they cannot separate us from the love of Christ. If we suffer with Christ (Rom 8:17) in these things, then we will be more than conquerors.
It is possible to fail this test of suffering with Christ by losing faith in God in our sufferings.

"Yea, i.e., assuredly, certainly, for thy sake, not for our offences, but for obeying thee; the trials of these suppliants came upon them because they were loyal to their God. ...
We are counted as sheep for the slaughter; as if we were only meant to be killed, and made on purpose to be victims; as if it were as easy and as innocent a thing to slay us as to slaughter sheep. In this and following verses we clearly hear the martyr's cry. From Piedmont and Smithfield, from St. Bartholomew's massacre and the dragoonades of Claverhouse [Sri Lanka, Sudan, Egypt, Syria, China ...], this appeal goes up to heaven, while the souls under the altar continue their solemn cry for vengeance. Not long shall the church plead in this fashion, her shame shall be recompensed, her triumph shall dawn." - Spurgeon

We recite every day in Shema the commandment to love Hashem ... with all your soul - even if it costs you your life. One who recites this with the sincere resolve to fulfill it if ever the occasion should arise is considered as if he is killed for God's sake all the time - Rashba
v23 The previous verse does not mean that we should be fatalistic about our sufferings. We should pray like the sons of Korah in this psalm.

"In persecuting times men are apt to cry, Where is the God of Israel? At the thought of what the saints have endured from their haughty enemies, we join our voices in the great martyr cry and sing with the bard of Paradise:
"Avenge, O Lord, thy slaughtered saints, whose bones
Lie scattered on the Alpine mountains cold;
Even those who kept thy truth so pure of old,
When all our fathers worshipped stocks and stones,
Forget not: in thy book record their groans
Who were thy sheep."  - John Milton (1608-74) On the Late Massacre in Piedmont  "
- Spurgeon

Though the Lord seems to sleep, it is in the stern of the boat. Do not be afraid. If He is with you, no storm can prevail to your destruction (Mk 4:40). - F.B. Meyer
v24 "Not petulantly, but piteously and inquiringly, we may question the Lord when his dealings are mysterious. We are permitted to order our case with arguments, and plead the right before the face of the august Majesty. Why, Lord, dost thou become oblivious of thy children's woes? This question is far more easily asked than answered; it is hard, indeed, in the midst of persecution to see the reason why we are left to suffer so severely." - Spurgeon
v25 "Our heart is low as low can be, as low as the dust beneath the soles of men's feet. When the heart sinks, the man is down indeed. Heart sorrow is the very heart of sorrow. ...
God's saints may be thus abject, they may be not only in the dust, but on the dunghill with Job and Lazarus, but their day cometh, and their tide will turn, and they shall have a brave summer after their bitter winter." - Spurgeon
v26 "A short, but sweet and comprehensive prayer, much to the point, clear, simple, urgent, as all prayers should be.
Here is the final plea. The favor is redemption, the plea is mercy; and this, too, in the case of faithful sufferers who had not forgotten their God. Mercy is always a safe plea, and never will any man find a better.
Here ends this memorable Psalm, but in heaven its power ends not, but brings down deliverance for the tried people of God." - Spurgeon