Isaiah 13:15

Every one that is found - In Babylon, or that is overtaken in fleeing from it. This is a description of the capture of the city, and of the slaughter that would ensue, when the invaders would spare neither age nor sex.

Every one that is joined unto them - Their allies and friends. There shall be a vast, indiscriminate slaughter of all that are found in the city, and of those that attempt to flee from it. Lowth renders this, ‘And all that are collected in a body;’ but the true sense is given in our translation. The Chaldee renders it, ‘And every one who enters into fortified cities shall be slain with the sword.’