“The noun occurs 66 times in the Old Testament, 58 times in poetry. The frequent prepositions with it show that it is the grave below the earth. The biblical poets use rich and varied figures to depict it. Sheol has a ‘mouth’ (Ps. 141:7), which it ‘enlarges’ (Isa. 5:14), and it is ‘never satisfied’ (Prov. 27:20; 30:16). It is so powerful that none escapes its ‘grip’ (Ps. 89:48; Song 8:6), but some are redeemed from it (Ps. 49:15; Prov. 25:14; Hos. 13:14). It is a like a prison with ‘cords’ (2 Sam. 22:6) and a land that has ‘gates’ (Isa. 38:10) with ‘bars’ (Job 17:16). Here corruption is ‘the father,’ and the worm ‘the mother and sister’ (Job 17:13ff). It is ‘a land’ of no return to this life (Job 7:9); an abode where socioeconomic distinctions cease. Rich and poor (Job 3:18-19), righteous and wicked (3:17) lie together. It is a land of silence (Ps. 94:17), darkness (13:3), weakness, and oblivion (88:11-19). The destructive nature of this realm is intensified by the addition of ‘Abaddon’ (Prov. 15:11; 27:20). One errs in using this figurative language to build a doctrine of the intermediate state. On the other hand, these vivid and powerful figures transform the grave from a six-foot pit to a metaphorical and transcendent realm distinct from life on top of the earth inhabited by living mortals and from heaven inhabited by the immortal God and his court. Those who descend there will never again participate in salvation history or join the holy throng at the earthly temple (Ps. 6:5; Isa. 38:18). Like the Jordan River and Mount Zion, the grave symbolizes eternal realities that transcend their physical space.”
—Bruce K. Waltke, The Book of Proverbs: Chapters 1—15 (Eerdmans 2004), 1:116.