Thomas Aquinas Commentary Lamentations 2:14

"Thy prophets have seen for thee false and foolish visions; And they have not uncovered thine iniquity, to bring back thy captivity, But have seen for thee false oracles and causes of banishment." — Lamentations 2:14 (ASV)

Here, the author identifies the cause of its incurability: the physicians of the time, namely the prophets, neglected to treat her.

First, he shows the falsehood of the prophets regarding the false things they predicted: your prophets have seen—that is, they claimed to have seen—false and foolish things, because it was foolish to believe that God would not punish sinners. Her prophets have daubed them without tempering the mortar (Ezekiel 22:28). But there were also false prophets among the people, even as there shall be among you lying teachers (2 Peter 2:1). Regarding the things they did not say, the text adds, and they have not laid open your iniquity. This was contrary to the command for a true prophet: Cry, cease not, lift up your voice like a trumpet, and show my people their wicked doings (Isaiah 58:1).

Second, he explains the kind of things seen in their false visions: but they have seen for you false assumptions, meaning overwhelming burdens, just as a burden carried higher weighs one down all the more. Thus says the Lord concerning the prophets that make my people err (Micah 3:5). They also saw Banishments, meaning liberations, such as the false promise: Even so will I break the yoke of Nebuchadnezzar the king of Babylon after two full years of days (Jeremiah 28:11). Alternatively, assumptions could mean that God would take you to Himself, and banishments could mean that your enemies would be expelled.