The ins and outs of Babylon

There is a famine and Isaac heads into the land of the Philistines,  which is sort of a Babylon.

In Revelation 18 we read
 ⁴ Then I heard another voice from heaven saying,
   “Come out of her, my people,
   lest you take part in her sins,
lest you share in her plagues;
⁵ for her sins are heaped high as heaven,
   and God has remembered her iniquities.

Reminded me of a book I read recently.