Midrash su Salmi 78:16

(Ibid.) "They stood up like a flask": Just as a bound flask neither emits nor admits, so, the spirits of the Egyptians were bound up within them, neither emitting nor admitting — while Israel ate and drank and rejoiced. Sweet water issued forth for them from salted water, viz. (Psalms 78:160) "and He brought forth nozlim from the rock," "nozlim" being living waters, as in (Song of Songs 4:15) "a garden spring, a well of living waters," and (Mishlei 5:15) "Drink water from your pit and nozlim from your well."

R. Judah declared: These ten verses are derived from various sources. It may be compared to a man traveling over a road, preceded by his son. If robbers approach from the front to seize the lad, he places him behind himself. If a wolf comes from behind to snatch him, he puts the lad in front of him. If he sees robbers behind him and the wolf before him, he takes his son in his arms. The Holy One, blessed be He, did likewise for Israel. When the sea was before them and the Egyptians behind, He bore them in His arms. When Israel began to suffer from the sun, He spread His cloak over them, as it is said: He spread a cloud for a screen (Ps. 105:39). When Israel became hungry, He gave them bread, as is stated: Behold, I will cause to rain bread from heaven for you (Exod. 16:4). When they became thirsty He gave them water, for He brought streams also out of the rock (Ps. 78:15).

"And you, raise your staff": Ten miracles were performed for Israel at the sea: The waters were split and became like a dome, viz. (Habakkuk 3:14) "You split (the sea) for his tribes; the summit of its scattering raged to scatter me"; the sea became dry land, viz. (Exodus 14:29) "and the children of Israel walked on the dry land"; it became like tar (where the Egyptians trod), viz. (Habakkuk, Ibid. 15) "You led your horses in the sea, in the mire of many waters"; it (the water) became like crumbs, viz. (Psalms 74:13) "You 'crumbed' the sea with Your might"; it became like rocks, viz. (Ibid.) "You broke the heads of serpents (the Egyptians) on the waters"; the sea split into sections, viz. (Ibid. 136:13) "You split the Red Sea into sections," viz. (Ibid. 15:8) "and with the breath of Your nostrils the waters piled up"; they became like a wall, viz. (Ibid.) "the waves stood up as a wall"; He extracted for them sweets from salts, viz. (Psalms 78:16) "and He brought forth streams from a rock and brought down waters as rivers"; He froze the sea for them and it became like vessels of glass, viz. (Exodus 15:8) "The depths froze in the midst of the sea."