Shared ground
Isaiah 13:17–18 presents the fall of a targeted group within the “oracle concerning Babylon” by naming a real-world attacker: the Medes. The text speaks as a divine announcement (“Behold… I will stir up”), so the coming invasion is framed as something God sets in motion, not a random turn of politics.
The Medes are described as unstoppable by negotiation: they “will not regard silver” and “will not delight in gold.” In the ancient setting, tribute could sometimes soften an enemy’s plans, but here wealth has no leverage.
The outcome is depicted as severe warfare. The focus on bows, the killing of young men, and the lack of pity for the unborn and children communicates a collapse of normal protections and a totalizing defeat.
Where interpretation differs (only where needed)
Who “them” is. Some read “them” narrowly as the people of Babylon in the immediate oracle. Others think the pronoun can reach beyond a single city to Babylon’s broader forces and dependents in the empire. Either way, the passage assumes the surrounding target is Babylon and its world.
How to understand “I will stir up.” Some take it as direct divine causation: God actively incites and directs the Medes’ assault. Others read it as purposeful divine governance: God “stirs up” by arranging events, removing restraints, or handing Babylon over, without portraying God as endorsing every atrocity described.
How literal the brutality language is. Many read v.18 as straightforward description of what happens in conquest. Others note that prophetic war language can intensify and compress horrors to communicate “no mercy” and “no safe category,” even if not every detail is meant as a report of specific incidents.
Why the disagreement exists
The text is terse and poetic, and it sits inside a long oracle using vivid military imagery. Pronouns (“them”), causation language (“stir up”), and stock conquest motifs (no pity for the vulnerable) can be read as either precise description or concentrated rhetoric. The passage itself does not stop to clarify these points.
What this passage clearly contributes
It links the coming downfall of Babylon to identifiable historical agents (the Medes), while still portraying the event as under divine initiative (“I will stir up”). It also stresses that Babylon’s collapse will not be avoidable through wealth or diplomacy. Finally, it refuses to romanticize war: the defeat is described as socially catastrophic, especially for those normally least able to protect themselves. See also the nearby parallel language in Isaiah 13:16.