The phrase 'Then shall ye know that I am the LORD' appears multiple times. What kind of 'knowing' is this, and why does it take such devastating events for them to understand?
This isn't the gentle, intimate knowledge of a disciple who walks closely with a beloved teacher. Instead, it's a harsh, experiential 'knowing' that comes through divine judgment.
Forced Recognition
Despite generations of prophets warning them, the people of Israel had largely ignored God. They continued in their idolatry, refusing to acknowledge the LORD's authority. The coming destruction—their slain lying among their idols—will be an undeniable, irrefutable proof of God's power and justice.
The Ungodly's Awareness
As one commentator noted, this 'experimental knowledge' is one that even the ungodly experience. It's the terrifying realization of God's might when His vengeance is so clear that even those who resisted Him are 'compelled to feel' His power and the justice of their punishment. This knowledge doesn't necessarily lead to repentance, but it does confirm God's identity as the sovereign LORD.