According to Parkhurst’s Greek and English Lexicon to the New Testament (London, 1845, p. 2), the Greek aʹbys·sos means “very or exceedingly deep.” According to Liddell and Scott’s Greek-English Lexicon (Oxford, 1968, p. 4), it means “unfathomable, boundless.” The Greek Septuagint uses it regularly to translate the Hebrew tehohmʹ (watery deep), as at Genesis 1:2; 7:11.

Aʹbys·sos occurs nine times in the Christian Greek Scriptures, seven of them being in the book of Revelation. It is from “the abyss” that the symbolic locusts come forth under the headship of their king, Abaddon or Apollyon, “the angel of the abyss.” (Re 9:1-3, 11) “The wild beast” that makes war against the “two witnesses” of God and kills them is also spoken of as coming “out of the abyss.” (Re 11:3, 7) Revelation 20:1-3 describes the future casting of Satan into the abyss for a thousand years; something that a legion of demons urged Jesus not to do to them on a certain occasion.​—Lu 8:31.

Scriptural Significance. It is noteworthy that the Greek Septuagint does not use aʹbys·sos to translate the Hebrew sheʼohlʹ, and in view of the fact that spirit creatures are cast into it, it cannot properly be limited in meaning to Sheol or Hades, inasmuch as these two words clearly refer to the common earthly grave of mankind. (Job 17:13-16; see HADES; SHEOL.) It does not refer to “the lake of fire,” since it is after Satan’s release from the abyss that he is thereupon hurled into the lake of fire. (Re 20:1-3, 7-10) Paul’s statement at Romans 10:7, in which he speaks of Christ as being in the abyss, also precludes such possibility and shows as well that the abyss is not the same as Tartarus.​—See TARTARUS.

 Romans 10:6, 7 aids in clearing up the meaning of “the abyss” in stating: “But the righteousness resulting from faith speaks in this manner: ‘Do not say in your heart, “Who will ascend into heaven?” that is, to bring Christ down; or, “Who will descend into the abyss?” that is, to bring Christ up from the dead.’” (Compare De 30:11-13.) It is evident that “the abyss” here refers to the place in which Christ Jesus spent part of three days and from which place his Father resurrected him. (Compare Ps 71:19, 20; Mt 12:40.) Revelation 20:7 refers to the abyss as a “prison,” and the confinement of absolute restraint resulting from death in the case of Jesus certainly harmonizes with this.​—Compare Ac 2:24; 2Sa 22:5, 6; Job 38:16, 17; Ps 9:13; 107:18; 116:3.

Concerning the root meaning “unfathomable” as characteristic of “the abyss,” it is of interest to note the statement in Hastings’ Encyclopædia of Religion and Ethics (1913, Vol. I, p. 54), which, in commenting on Romans 10:6, 7, says: “The impression conveyed by St. Paul’s language is of the vastness of that realm, as of one that we should vainly attempt to explore.” Paul contrasts the inaccessibility of “heaven” and of the “abyss” with the accessibility of righteousness by faith. The use of the related word baʹthos made by Paul at Romans 11:33 illustrates this: “O the depth [baʹthos] of God’s riches and wisdom and knowledge! How unsearchable his judgments are and past tracing out his ways are!” (See also 1Co 2:10; Eph 3:18, 19.) So, in harmony with Romans 10:6, 7, the place that is represented by “the abyss” would also evidently imply being out of the reach of anyone but God or his appointed angel with “the key of the abyss.” (Re 20:1) Liddell and Scott’s Greek-English Lexicon (p. 4) gives as one of the meanings of the word aʹbys·sos “the infinite void.”

The plural form of the Hebrew word metsoh·lahʹ (or metsu·lahʹ) is translated “large abyss” in Psalm 88:6 and literally means “abysses,” or “depths.” (Compare Zec 10:11.) It is related to tsu·lahʹ, meaning “watery deep.”​—Isa 44:27.