For The Truth's Sake, Christians rejoice in blessed assurance. This confidence cannot exist on a true foundation while we live in sin. Before forgiveness of his sin, David said, "When I kept silence, my bones waxed old through my roaring (groaning) all the day long." After forgiveness he exclaimed, "Blessed is he whose transgression is forgiven, whose sin is covered" (Ps. 32). While living as "children of disobedience," we are "by nature" of such living, "the children of wrath . . . having no hope, and without God in the world" (Eph. 2:1-13). Only fear and trembling can abide in a soul where there is "a certain fearful looking for of judgment and fiery indignation, which shall devour the adversaries . . . It is a fearful thing to fall into the hands of the living God . . . For our God is a consuming fire" (Heb. 11:27, 31; 12:29).
No wonder Jesus said, "Come unto me, all ye that labor and are heavy laden, and I will give you rest" (Matt. 11:28). The first gospel sermon was preached on Pentecost after Jesus ascended to heaven. When people heard that He is "both Lord and Christ" and saw their weight of sin, "they were pricked in their heart" and cried out to be forgiven. The call of Jesus was given for them to come and receive rest to their souls: "Repent, and be baptized every one of you in the name of Jesus Christ, for the remission of sins . . ." (Acts 2:26-38). Through the gospel, Christ calls sinners to come by "the faith of the operation of God," being "buried with him in baptism" (Col. 2:12). When risen from the waters of baptism, they may go on their way "rejoicing" (Acts 8:35-39). When Christians stumble into sin again, they may confess their wrongs and pray God's forgiveness: "the blood of Jesus Christ his Son cleanseth us from all sin" (1 Jn. 1:6-10).
Assurance in Christ is based upon the certainty of God's Word — "the Word of the truth of the gospel" (Col. 1:5). God who "cannot lie" has spoken through His Son in His Word; with God there is "no variableness, neither shadow of turning" (Tit. 1:2; Jas. 1:17). Assurance is well founded when we "speak as the oracles of God" (1 Pet. 4:11) — speak where the Bible speaks and are silent where it is — call Bible things by Bible names — give Book, Chapter, and Verse for all we do in serving God.
False assurance is often given. Men claim that after they become Christians they can never fall from God's grace. Paul said of certain ones who were altering the gospel, "Ye are fallen from grace" (Gal. 5:4). Christians who claim "fellowship" with God, claim, "I know Him," and claim to abide "in Him," but who continue to walk in their sins are really "of the devil" (1 Jn. 1:6; 2:3-6; 3:8). "He that doeth good is of God: but he that doeth evil hath not seen God" (3 Jn. 11). Jesus came to destroy sin; we must put it away if we are to have assurance in Him.
Assurance based on any foundation other than God's Word is not true assurance in Christ. Men often express confidence upon false foundations: "How could so many be wrong?. . . I think, suppose, guess . . . It's what you feel in your heart . . . Our sacred tradition says . . .Our preacher is such a nice man and he says . . . The scholars who wrote our creed believed . . . Our latest convention voted . . .Whatever was good enough for grandma is good enough for me . . . Etc. . . ."