You have seen all their vengeance, all their plots against me.
This mode of speaking was often used by the saints, because God, when it pleased him to look on their miseries, was ever ready to bring them help. Nor were they words without meaning, when the faithful said, O Lord, thou hast seen; for they said this for their own sake, that they might shake off all unbelief.
We may observe throughout this chapter a struggle in the prophet's breast between sense and faith, fear and hope; he complains and then comforts himself, yet drops his comforts and returns again to his complaints, as Psa 42:1-11. But, as there, so here, faith gets the last word and comes off a conqueror; for in these verses he concludes with some comfort.
Commenting on Lamentations 3:55-66
Persecute and destroy them in anger,.... As they have persecuted the people of God, do thou persecute them; and never leave pursuing them untie thou hast made a full end of them, as the effect of vindictive wrath and vengeance: from under the heavens of the Lord; which are made by him, and in which he dwells; let them not have the benefit of them...