The word, “Sheol”, is mentioned sixty-five times in the Old Testament. Sheol was the place in the lowest parts of the earth where ancient Jewish scholars believed that both righteous and unrighteous persons went after death. In the Psalms, Sheol is described as a place without light and sound that is cut off from life and from the Hebrew God. The inhabitants of Sheol were called “shades” - weak, trembling entities without personality or strength. In a forbidden practice, the shades could be contacted by the living, as the Witch of Endor contacted the shade of the prophet Samuel for King Saul. Contrariwise, by the time of Jesus, it was common for Jews to believe that the righteous dead go to a place of comfort while the wicked go to Hades (Sheol). “Selah” is another word used seventy-four times in the Old Testament, primarily in the Psalms (seventy-one times). Its meaning is not precisely known, but it is probably an instruction by the psalmist to “stop and listen”. Since the Psalms were often sung accompanied by musical instruments, Selah may also indicate a pause in the song to stress the importance of the preceding passage.
~Dr. Gil Haas