Just some notes about Quranic "rivers that flow beneath" that I noticed this morning. What struck me as most odd was that Pharaoh used the same expression, that he had rivers that flowed beneath him! (in 43:51)
"Rivers that flow beneath"
The rivers are described as having water, milk, wine and honey:
47:15 Is the example of Paradise; that the righteous have been promised with rivers of pure water, and rivers of milk whose taste does not change, and rivers of wine that are delicious for the drinkers, and rivers of strained honey, and for them in it are all kinds of fruits, and a forgiveness from their Lord; like that of those who abide in the Fire, and are given to drink boiling water that cuts-up their intestines?
The rivers (l-anhāru) (or the Jannatin) contain fruit (thamaratin) as provision (riz'qan) (2:25 - see "minha" and query the masculine/feminine sing/plural preposition)
2:25 And give good news to those who believe and do good works that they will have jannātin with rivers flowing beneath. Every time they receive of its fruit, they say: "This is what we have been provisioned before," and they are given its likeness. And there they will have pure spouses, and in it they will abide.
Generations from before had these rivers flowing beneath them:
6:6 Did they not see how many generations We have destroyed before them? We granted them dominance over the land more than what We granted you, and We sent the clouds to them abundantly, and We made rivers flow beneath them; then We destroyed them for their sins, and established after them a new generation.
Pharaoh had rivers that flowed beneath him:
43:51 And Pharaoh proclaimed among his people: "O my people, do I not possess the kingship of Egypt, and these rivers that flow below me? Do you not see?"