Thomas Aquinas Commentary Lamentations 1:19

"I called for my lovers, [but] they deceived me: My priests and mine elders gave up the ghost in the city, While they sought them food to refresh their souls." — Lamentations 1:19 (ASV)

Here he laments the wasting away of those who have starved to death during the siege.

1. He notes the disappointment caused by friends, my friends, the Egyptians, because they did not help as he had hoped. For Egypt shall help in vain, and to no purpose: therefore have I cried concerning this (Isaiah 30:7).
2. He describes the wasting away caused by this: priests, for whom this is especially shameful, wasted away from hunger. Their nobles have perished with famine (Isaiah 5:13).
3. He gives the reason for this wasting away: because they sought food simply to be revived, not to be filled, and they did not find it. Alternatively, he identifies the reason for their fault: they searched for food for themselves and not for the people. Woe to the shepherds of Israel, that fed themselves (Ezekiel 34:2).