A Commentary, Critical, Practical, and Explanatory on the Old and New Testaments, by Robert Jamieson, A.R. Fausset and David Brown  at sacred-texts.com
lam 4:1THE SAD CAPTURE OF JERUSALEM, THE HOPE OF RESTORATION, AND THE RETRIBUTION AWAITING IDUMEA FOR JOINING BABYLON AGAINST JUDEA. (Lam. 4:1-22)
gold--the splendid adornment of the temple [CALVIN] (Lam 1:10; Kg1 6:22; Jer 52:19); or, the principal men of Judea [GROTIUS] (Lam 4:2).
stones of . . . sanctuary--the gems on the breastplate of the high priest; or, metaphorically, the priests and Levites.
lam 4:2comparable to . . . gold-- (Job 28:16, Job 28:19).
earthen pitchers-- (Isa 30:14; Jer 19:11).
lam 4:3sea monsters . . . breast--Whales and other cetaceous monsters are mammalian. Even they suckle their young; but the Jewish women in the siege, so desperate was their misery, ate theirs (Lam 4:10; Lam 2:20). Others translate, "jackals."
ostriches--see on Job 39:14; Job 39:16, on their forsaking their young.
lam 4:4thirst--The mothers have no milk to give through the famine.
lam 4:5delicately--on dainties.
are desolate--or, "perish."
in scarlet embrace dunghills--Instead of the scarlet couches on which the grandees were nursed, they must lie on dunghills.
embrace--They who once shrank sensitively from any soil, gladly cling close to heaps of filth as their only resting-place. Compare "embrace the rock" (Job 24:8).
lam 4:6greater than . . . Sodom-- (Mat 11:23). No prophets had been sent to Sodom, as there had been to Judea; therefore the punishment of the latter was heavier than that of the former.
overthrown . . . in a moment--whereas the Jews had to endure the protracted and manifold hardships of a siege.
no hands stayed on her--No hostile force, as the Chaldeans in the case of Jerusalem, continually pressed on her before her overthrow. Jeremiah thus shows the greater severity of Jerusalem's punishment than that of Sodom.
lam 4:7Nazarites--literally, "separated ones" (Num 6:2). They were held once in the highest estimation, but now they are degraded. God's blessing formerly caused their body not to be the less fair and ruddy for their abstinence from strong drink. Compare the similar case of Daniel, &c. (Dan 1:8-15). Also David (Sa1 16:12; Sa1 17:42). Type of Messiah (Sol 5:10).
rubies--GESENIUS translates, "corals," from a Hebrew root, "to divide into branches," from the branching form of corals.
polishing--They were like exquisitely cut and polished sapphires. The "sapphires" may represent the blue veins of a healthy person.
lam 4:8blacker than . . . coal--or, "than blackness" itself (Joe 2:6; Nah 2:10).
like a stick--as withered as a dry stick.
lam 4:9The speedy death by the sword is better than the lingering death by famine.
pine away--literally, "flow out"; referring to the flow of blood. This expression, and "stricken through," are drawn from death by "the sword."
want of . . . fruits--The words in italics have to be supplied in the original (Gen 18:28; Psa 109:24).
lam 4:10(Lam 2:20; Deu 28:56-57).
pitiful--naturally at other times compassionate (Isa 49:15). JOSEPHUS describes the unnatural act as it took place in the siege under Titus.
lam 4:11fire . . . devoured . . . foundations-- (Deu 32:22; Jer 21:14). A most rare event. Fire usually consumes only the surface; but this reached even to the foundation, cutting off all hope of restoration.
lam 4:12Jerusalem was so fortified that all thought it impregnable. It therefore could only have been the hand of God, not the force of man, which overthrew it.
lam 4:13prophets--the false prophets (Jer 23:11, Jer 23:21). Supply the sense thus: "For the sins . . . these calamities have befallen her."
shed the blood of the just-- (Mat 23:31, Mat 23:37). This received its full fulfilment in the slaying of Messiah and the Jews' consequent dispersion (Jam 5:6).
lam 4:14blind--with mental aberration.
polluted . . . with blood--both with blood of one another mutually shed (for example, Jer 2:34), and with their blood shed by the enemy [GLASSIUS].
not touch . . . garments--as being defiled with blood (Num 19:16).
lam 4:15They . . . them--"They," that is, "men" (Lam 4:14). Even the very Gentiles, regarded as unclean by the Jews, who were ordered most religiously to avoid all defilements, cried unto the latter, "depart," as being unclean: so universal was the defilement of the city by blood.
wandered--As the false prophets and their followers had "wandered" blind with infatuated and idolatrous crime in the city (Lam 4:14), so they must now "wander" among the heathen in blind consternation with calamity.
they said--that is, the Gentiles said: it was said among the heathen, "The Jews shall no more sojourn in their own land" [GROTIUS]; or, wheresoever they go in their wandering exile, "they shall not stay long" [LUDOVICUS DE DIEU], (Deu 28:65).
lam 4:16Ain and Pe are here transposed (Lam 4:16-17), as in Lam 2:16-17; Lam 3:46-51.
anger--literally, "face"; it is the countenance which, by its expression, manifests anger (Psa 34:16). GESENIUS translates, "the person of Jehovah"; Jehovah present; Jehovah Himself (Exo 33:14; Sa2 17:11).
divided--dispersed the Jews.
they respected not . . . priests--This is the language of the Gentiles. "The Jews have no hope of a return: for they respected not even good priests" (Ch2 24:19-22) [GROTIUS]. MAURER explains it, "They (the victorious foe) regard not the (Jewish) priests when imploring their pity" (Lam 5:12). The evident antithesis to "As for us" (Lam 4:17) and the language of "the heathen" at the close of Lam 4:15, of which Lam 4:16 is the continuation, favor the former view.
lam 4:17As for us--This translation forms the best antithesis to the language of the heathen (Lam 4:15-16). CALVIN translates, "While as yet we stood as a state, our eyes failed," &c.
watched for a nation that could not save us--Egypt (Kg2 24:7; Isa 30:7; Jer 37:5-11).
lam 4:18They--the Chaldeans.
cannot go--without danger.
lam 4:19The last times just before the taking of the city. There was no place of escape; the foe intercepted those wishing to escape from the famine-stricken city, "on the mountains and in the wilderness."
swifter . . . than . . . eagles--the Chaldean cavalry (Jer 4:13).
pursued--literally, "to be hot"; then, "to pursue hotly" (Gen 31:36). Thus they pursued and overtook Zedekiah (Jer 52:8-9).
lam 4:20breath . . . anointed of . . . Lord--our king, with whose life ours was bound up. The original reference seems to have been to Josiah (Ch2 35:25), killed in battle with Pharaoh-necho; but the language is here applied to Zedekiah, who, though worthless, was still lineal representative of David, and type of Messiah, the "Anointed." Viewed personally the language is too favorable to apply to him.
live among the heathen--Under him we hoped to live securely, even in spite of the surrounding heathen nations [GROTIUS].
lam 4:21Rejoice--at our calamities (Psa 137:7). This is a prophecy that Edom should exult over the fall of Jerusalem. At the same time it is implied, Edom's joy shall be short-lived. Ironically she is told, Rejoice while thou mayest (Ecc 11:9).
cup--for this image of the confounding effects of God's wrath, see Jer 13:12; Jer 25:15-16, Jer 25:21; as to Edom, Jer. 49:7-22.
lam 4:22(Isa 40:2). Thou hast been punished enough: the end of thy punishment is at hand.
no more carry thee . . . into captivity--that is, by the Chaldeans. The Romans carried them away subsequently. The full accomplishment of this prophecy must therefore refer to the Jews' final restoration.
discover--By the severity of His punishments on thee, God shall let men see how great was thy sin (Jer 49:10). God "covers" sin when He forgives it (Psa 32:1, Psa 32:5). He "discovers," or "reveals," it, when He punishes it (Job 20:27). Jer 49:10 shows that Margin is wrong, "carry captive" (this rendering is as in Nah 2:7; compare "discovered," Margin).