2402. 'For Jehovah is destroying the city' means that they would inevitably perish. This is clear from the explanation of practically the same words in 2395, 2397.

511. And great fear fell on those who saw them. This symbolizes a disturbance of the mind and alarm at Divine truths.

The symbolic meaning of fear varies, depending on what it affects. Here it symbolizes a disturbance of the mind and alarm at Divine truths, as Divine truths have this effect on evil people. For evil people are terrified as soon as they hear about hell and eternal damnation. But the terror soon dissipates, along with their belief in the existence of any life after death.