May be simply defined as the termination of life. It is represented under a variety of aspects in Scripture: (1.) “The dust shall return to the earth as it was” (Eccl. 12:7). (2.) “Thou takest away their breath, they die” (Ps. 104:29). (3.) It is the dissolution of “our earthly house of this tabernacle” (2 Cor. 5:1); the “putting off this tabernacle” (2 Pet. 1:13, 14). (4.) Being “unclothed” (2 Cor. 5:3, 4). (5.) “Falling on sleep” (Ps. 76:5; Jer. 51:39; Acts 13:36; 2 Pet. 3:9. (6.) “I go whence I shall not return” (Job 10:21); “Make me to know mine end” (Ps. 39:4); “to depart” (Phil. 1:23). The grave is represented as “the gates of death” (Job 38:17; Ps. 9:13; 107:18). The gloomy silence of the grave is spoken of under the figure of the “shadow of death” (Jer. 2:6). Death is the effect of sin (Heb. 2:14), and not a “debt of nature.” It is but once (9:27), universal (Gen. 3:19), necessary (Luke 2:28-30). Jesus has by his own death taken away its sting for all his followers (1 Cor. 15:55-57). There is a spiritual death in trespasses and sins, i.e., the death of the soul under the power of sin (Rom. 8:6; Eph. 2:1, 3; Col. 2:13). The “second death” (Rev. 2:11) is the everlasting perdition of the wicked (Rev. 21:8), and “second” in respect to natural or temporal death. THE DEATH OF CHRIST is the procuring cause incidentally of all the blessings men enjoy on earth. But specially it is the procuring cause of the actual salvation of all his people, together with all the means that lead thereto. It does not make their salvation merely possible, but certain (Matt. 18:11; Rom. 5:10; 2 Cor. 5:21; Gal. 1:4; 3:13; Eph. 1:7; 2:16; Rom. 8:32-35).
–Easton's Bible Dictionary