This is an article from the public domain Easton's Bible Dictionary, originally published in 1897. This article is written from a nineteenth century Christian viewpoint, and may not reflect modern opinions or recent discoveries in Biblical scholarship. Please help the Wikipedia by bringing this article up to date.

Perseverance of the saints - their certain continuance in a state of grace. Once justified and regenerated, the believer can neither totally nor finally fall away from grace, but will certainly persevere therein and attain everlasting life.

This doctrine is clearly taught in these passages, John 10:28, 29; Rom. 11:29; Phil. 1:6; 1 Pet. 1:5. It, moreover, follows from a consideration of (1) the immutability of the divine decrees (Jer. 31:3; Matt. 24:22-24; Acts 13:48; Rom. 8:30); (2) the provisions of the covenant of grace (Jer. 32:40; John 10:29; 17:2-6); (3) the atonement and intercession of Christ (Isa. 53:6, 11; Matt. 20:28; 1 Pet. 2:24; John 11:42; 17:11, 15, 20; Rom. 8:34); and (4) the indwelling of the Holy Ghost (John 14:16; 2 Cor. 1:21, 22; 5:5; Eph. 1:14; 1 John 3:9).

This doctrine is not inconsistent with the truth that the believer may nevertheless fall into grievous sin, and continue therein for some time. (See Backslide[?].)

From Easton's Bible Dictionary (1897)