Charles Ellicott Commentary Jeremiah 50:15

"Shout against her round about: she hath submitted herself; her bulwarks are fallen, her walls are thrown down; for it is the vengeance of Jehovah: take vengeance upon her; as she hath done, do unto her." — Jeremiah 50:15 (ASV)

She has given her hand. —The words paint the attitude of one who submits and stretches out his hand, as a sign that he gives himself into the power of the conqueror. (2 Chronicles 30:8; Lamentations 5:6.) So in Latin, “ dare manum ” was a synonym for submission (Cicero, De Amicitia 26).

Her foundations are fallen. —Better, with the Septuagint, bastions or bulwarks.

As she has done, do unto her. —We note an identity of thought and almost of language with Psalms 137:8. Had the Psalmist heard the prophecy, or the prophet the psalm? The former seems the more probable alternative.