Answer
In Noahās time, when the great flood destroyed the earth, the floodwaters poured forth from two sources: rainfall from above and, from below, vast amounts of subterranean water rising to the surface. Moses records what happened this way: āAll the fountains of the great deep were broken up, and the windows of heaven were openedā (Genesis 7:11, NKJV).
The āfountains of the great deepā (ESV, NKJV, NASB) and the āwindows of the heavensā (ESV) describe the origins of water that supplied the great flood. The global catastrophe occurred when āall the underground waters erupted from the earth,ā and āthe rain fell in mighty torrents from the sky,ā and the flood waters rose (Genesis 7:11, NLT). āFor forty days the flood kept coming on the earth, and . . . the waters increasedā (verse 17). The earth was thrown into chaos, and all the landās inhabitants except Noah and his family were swept away. But then āthe fountains of the deep and the windows of the heavens were closed,ā and āthe rain from the heavens was restrainedā (Genesis 8:2, ESV). The waters began to recede.
The word translated as ādeepā (³Ł±š³óĆ“³¾ in Hebrew) in Genesis 7:11 and 8:2 also appears in the creation account (see Genesis 1:2) and in the Song of Moses remembering the drowning of Pharoahās army in the Red Sea (see Exodus 15:5, 8). The word means āoceanā or āsea depthsā and carries the sense of unfathomed waters (Psalm 104:6–9; Job 38:16; Jonah 2:3). It is sometimes used metaphorically in Scripture for desperate circumstances (Psalm 18:16; 30:1; 69:2, 15; 2 Samuel 22:17). Given its biblical association with catastrophic events and as the source of divine punishment, itās unsurprising that the āgreat deepā is also a metaphor for Godās righteous judgments in Psalm 36:6.
The word translated as āfountainā (³¾²¹āyɲŌÅṯ in Hebrew) in Genesis 7:11 and 8:2 refers to a natural flow of groundwater, such as a spring or headwater. The image of a fountain or spring is used figuratively throughout the Bible to represent God (Psalm 36:9; Jeremiah 2:13), wisdom (Proverbs 10:11; 13:14; 14:27; 16:22; 18:4), a spouse (Proverbs 5:18), prosperity (Hosea 13:15), the fear of the Lord (Proverbs 14:27), life (Ecclesiastes 12:6), and eternal life (Revelation 7:17; 21:6).
The exact phrase fountain of the deep only appears in the flood account and in wisdom literature. Proverbs 8:22–31 ties the wisdom of God with creation and draws readers back to some of the events of Genesis, including the creation of the firmament, the sky, and āthe fountains of the deepā (verse 28, ESV).
When the time came for God to judge the world, He sent rain—lots of it—and He also brought floodwaters up from a place below the earth. The āfountains of the great deepā were broken up, releasing the pent-up water below and allowing it to gush up onto dry ground.