Exodus 8:2,3

All thy borders All the land that is within thy borders. And the river Nile, under which are comprehended all other rivers, streams, and ponds, as appears from Exodus 8:5. But the Nile is particularly mentioned, because God would make that an instrument of their punishment and misery, in which they most gloried, (Ezekiel 29:3,) to which they gave divine honours, and which was the instrument of their cruelty against the Israelites, Exodus 1:22. Frogs shall go into thy bed-chamber This plague was worse than the former, because it was more constant and more general: for the former in the waters did only molest them when they went to drink or use the water; but this troubled them in all places, and at all times, and annoyed all their senses with their filthy substance, shape, and noise, mingling themselves with their meats and drinks, and crawling into their beds, so that they could rest or be free from them nowhere. Into thine ovens They shall come up in such swarms as even to enter the driest places, which they naturally shun.