Thomas Aquinas Commentary Lamentations 1:17

"Zion spreadeth forth her hands; there is none to comfort her; Jehovah hath commanded concerning Jacob, that they that are round about him should be his adversaries: Jerusalem is among them as an unclean thing." — Lamentations 1:17 (ASV)

Here he weeps over the second captivity, which took place under Zedekiah when all the people were taken captive. Concerning this, he does three things.

1. He weeps over the siege.
2. He weeps over the captivity, at the words the LORD is just (Lamentations 1:18).
3. He weeps over the wasting away by starvation, at the words I called for my friends (Lamentations 1:19).

Concerning the first point, he does three things.

1. He presents the defection of her friends who should have come to her rescue and prevented the siege: Zion has spread forth her hands, as if calling for help from the Egyptians (see We have given our hand to Egypt, and to the Assyrians, Lamentations 5:6) or from God (see When you stretch forth your hands, I will turn away my eyes, Isaiah 1:15).
2. He presents the arrival of his enemies: the LORD commanded in dispensing justice for his enemies, the Chaldeans, to be round about him to besiege him. As it is written, I will give him a charge against the people of my wrath, to take away the spoils (Isaiah 10:6).
3. He presents the vileness of the besieged: Jerusalem is as a woman polluted—no one goes to her to defend her. See also Jeremiah 2:24: All that seek her shall not fail.