It is clear that the New Testament Greek word, Hades, refers to the same place as the Old Testament Hebrew word Sheol. For proof of this, all we need do is compare Psalm 16:10 with Acts 2:27 where it is quoted:

Thou wilt not abandon my soul to Sheol; neither wilt Thou allow Thy Holy One to undergo decay (Ps. 16:10, emphasis added).

Because Thou wilt not abandon my soul to Hades, nor allow Thy Holy One to undergo decay (Acts 2:27, emphasis added).

This being so, it is interesting that in all ten instances where Hades is mentioned in the New Testament, it is always spoken of in a negative sense and often as a tormenting place where the wicked are incarcerated after death (see Matt. 11:23; 16:18; Luke 10:15; 16:23; Acts 2:27; 2:31; Rev. 1:18; 6:8; 20:13-14). Again, all of this indicates that Sheol/Hades was and is an after-death abode for the unrighteous, a place of torment. [1]

[1] Some try to make a case by means of a few scriptures, such as Gen. 37:35, Job 14:13, Ps. 89:48, Eccl. 9:10 and Isa. 38:9-10, that Sheol was a place that the righteous also went after their deaths. The scriptural evidence for this idea is not very compelling. If Sheol was a place where both unrighteous and righteous went at death, then Sheol must have consisted of two separate compartments, one a hell and one a paradise, which is what is usually argued by the proponents of this idea.