As you probably read in your introductions to Lamentations, the book consists of five poems lamenting the destruction of Jerusalem. JPS notes that from ancient times authorship of these poems has been ascribed to Jeremiah, but recent scholars, according to JPS, believe the works to be anonymous compositions from the period of the Babylonian exile, following the fall of the Temple but prior to the return to Jerusalem.
The introduction contains this statement:
All of this outpouring is addressed to God, so that He may feel the suffering of His people, rescue them, and restore them to their country and to their former relationship with Him. The entire book may be thought of as an appeal for God’s mercy. Yet God remains silent.
The poems follow the curse theology of Deuteronomy in which God is entirely justified in raining destruction down upon His people due to their failure to follow His Law, in particular their idolatry. We see in the first two chs. several statements that God is entirely justified in bringing about this suffering. Moreso, though, we see the enormity of the pain the people experienced. Two of the five poems start with the exclamation “Alas!”
We also see, as in the final vv. of the first poem, calls for vengeance against the nations who perpetrated God’s vengeance. Clearly the authors ascribe the intent and source of their suffering to God’s righteous vengeance, but they also recognize that God used foreign nations to carry out the destruction. Interestingly, the authors ask God to inflict His vengeance upon those other nations, though they were but pawns in this drama. The poems never call for vengeance against God who actually caused the calamity.
It seems that the last time I read this book, a couple years back with the 66 Books in 52 Weeks group, I felt that the Lamentations were not as harsh as I had expected. Now, however, I find them to be quite gruesome. Ch. 2, for instance mentions women holding their infants as the children die, either of hunger or disease (v. 12), then describes the cannibalism that follows (v. 20)! These are not poems for the faint-hearted.