The Lord has made her suffer for the multitude of her transgressions. (NRSV 1:5)
The Lord hath afflicted her for the multitude of her transgressions. (KJV 1:5)
Okay, so why has God allowed all this terrible stuff to happen? Because the people of Jerusalem are sinners. But what did they do? Did they cheat on God with other gods?
Jerusalem sinned grievously, so she has become a mockery; all who honored her despise her, for they have seen her nakedness; she herself groans, and turns her face away. Her uncleanness was in her skirts; she took no thought of her future. (NRSV 1:8-9)
Jerusalem hath grievously sinned; therefore she is removed: all that honoured her despise her, because they have seen her nakedness: yea, she sigheth, and turneth backward. Her filthiness is in her skirts; she remembereth not her last end; therefore she came down wonderfully: she had no comforter. O Lord, behold my affliction: for the enemy hath magnified himself. (KJV 1:8-9)
The Poet never specifies exactly what the peoples' crimes were, but here he hints that it must have been something pretty terrible and the people realize it. Now, everyone has seen Jerusalem naked. So embarrassing.
My transgressions were bound into a yoke; by his hand they were fastened together; they weigh on my neck, sapping my strength. (NRSV 1:14)
The yoke of my transgressions is bound by his hand: they are wreathed, and come up upon my neck: he hath made my strength to fall. (KJV 1:14)
Sin is a powerful thing. The Poet describes it as a weight around their necks. It's like an anchor dragging them to the bottom of the ocean. Thinking about your transgressions has a huge emotional effect. That's part of the point of reading Lamentations.
The Lord is in the right, for I have rebelled against his word. (NRSV 1:18)
The Lord is righteous; for I have rebelled against his commandment. (KJV 1:18)
In case you're wondering if God is being a bit too harsh on these sinners, he's not. The people did the crime now they've got to do the time. God's just following through.
Deal with them as you have dealt with me because of all my transgressions; for my groans are many and my heart is faint. (NRSV 1:22)
Do unto them, as thou hast done unto me for all my transgressions: for my sighs are many, and my heart is faint. (KJV 1:22)
The Poet would like to point out that the Jewish people are not the only sinners in the house. Their enemies are pretty awful, too, and God's given them a victory. Maybe it's time for some payback? Just a suggestion, Lord.
Your prophets have seen for you false and deceptive visions; they have not exposed your iniquity to restore your fortunes, but have seen oracles for you that are false and misleading. (NRSV 2:14)
Thy prophets have seen vain and foolish things for thee: and they have not discovered thine iniquity, to turn away thy captivity; but have seen for thee false burdens and causes of banishment. (KJV 2:14)
Here's the only specific accusation. Apparently, in the time leading up to the invasion of Jerusalem, the prophets were telling people that things would be cool and they should just keep doing what they were doing. A good prophet would have pointed out that the people were sinning and that bad things were going to happen—that's the job description. Give those guys a job on Wall Street.
Cry aloud to the Lord! O wall of daughter Zion! Let tears stream down like a torrent day and night! Give yourself no rest, your eyes no respite! Arise, cry out in the night, at the beginning of the watches! Pour out your heart like water before the presence of the Lord! (NRSV 2:18-19)
Their heart cried unto the Lord, O wall of the daughter of Zion, let tears run down like a river day and night: give thyself no rest; let not the apple of thine eye cease. Arise, cry out in the night: in the beginning of the watches pour out thine heart like water before the face of the Lord. (KJV 2:18-19)
So, what can the people do now? The Poet recommends that they weep constantly about their sins and pray that God hasn't totally turned his back on them. this is the beginning of any reconciliation.
Why should any who draw breath complain about the punishment of their sins? Let us test and examine our ways, and return to the Lord[…] We have transgressed and rebelled, and you have not forgiven. You have wrapped yourself with anger and pursued us, killing without pity. (NRSV 3:39-40, 42-43)
Wherefore doth a living man complain, a man for the punishment of his sins? Let us search and try our ways, and turn again to the Lord[…] We have transgressed and have rebelled: thou hast not pardoned. Thou hast covered with anger, and persecuted us: thou hast slain, thou hast not pitied. (KJV 3:39-40, 42-43)
Complaining about your punishment isn't the same as crying out in pain. You can accept the consequences of your actions but still lament to God about your suffering.
It was for the sins of her prophets and the iniquities of her priests, who shed the blood of the righteous in the midst of her. Blindly they wandered through the streets, so defiled with blood that no one was able to touch their garments. "Away! Unclean!" people shouted at them; "Away! Away! Do not touch!" (NRSV 4:13-15)
For the sins of her prophets, and the iniquities of her priests, that have shed the blood of the just in the midst of her, They have wandered as blind men in the streets, they have polluted themselves with blood, so that men could not touch their garments. They cried unto them, Depart ye; it is unclean; depart, depart, touch not. (KJV 4:13-15)
Another answer to the "why?" question. The religious leaders in the city have totally failed the people. They lead lives of sin and steered everyone down the wrong path. God was not amused. But why not punish only the priest and prophets?
The punishment of your iniquity, O daughter Zion, is accomplished[…] but your iniquity, O daughter Edom, he will punish, he will uncover your sins. (NRSV 4:22)
The punishment of thine iniquity is accomplished, O daughter of Zion[…] he will visit thine iniquity, O daughter of Edom; he will discover thy sins. (KJV 4:22)
So, Jerusalem did wrong and they were punished. Luckily, it's all over. Now, it's some other sinful nation's turn. We're looking at you Edom.
The crown has fallen from our head; woe to us, for we have sinned! (NRSV 5:16)
The crown is fallen from our head: woe unto us, that we have sinned! (KJV 5:16)
Judah's current miserable state is even worse because of how far they've fallen. They were the chosen beloveds and now they're less than zero.