Danger of neglecting so Great Salvation, first spoken by Christ—To whom, not to Angels, the New Dispensation was subjected. Heb. 2:3-4
“How shall we escape, if we neglect so great salvation?“which at the first began to be spoken by the Lord” Mat. 4:17, Lk. 24:19. Mk. 16:15–19, Lk. 1:2; 24:47, 48, Ac. 1:22—the reference being to His preaching of the Gospel. By a metonymy, the Gospel, that reveals and proclaims God’s salvation, is here meant. In Ephesians 1:13 it is styled “The gospel of your salvation,” in Acts 13:26 the “word of this salvation,” in Romans 1:16 it is called “the power of God unto salvation to everyone that believeth,” and in Titus 2:11, “the grace of God which bringeth salvation.” The Gospel dispensation is denominated “the Day of Salvation” (2 Cor. 6:2). Ministers of the Gospel are they “which show unto us the way of salvation” (Acts 16:17).
That word was spoken before the time of the Gospel’s publication (note that the term “Gospel” is never once found in the Old Testament), and obviously signified the Law. Fitly may the Gospel be styled “salvation:” first, because in opposition to the Law (which was a “ministration of condemnation” 2 Cor. 3:9), it is a ministration of salvation. Second, because the Author of the Gospel is “salvation” itself: see Luke 2:30, John 4:22, etc., where “salvation” is synonymous with “the Savior.” Third, because whatever is needful to a knowledge of salvation is contained in the Gospel. Fourth, because the Gospel is God’s appointed means of salvation: see 1 Corinthians 1:21. True, in Old Testament times God’s elect had and knew the Gospel—Galatians 3:16; Hebrews 4:2—yet it was not publicly proclaimed and fully expounded. They had it under types and shadows, and in promises and prophecies. Dr. J. Brown has well said: “The ‘salvation’ here, then, is the deliverance of men through the mediation of Jesus Christ. This salvation is spoken of by the Apostle as unspeakably great: not merely a great salvation, nor even the great salvation but ‘so great salvation’—an expression peculiarly fitted to express his high estimate of its importance.” Pink Arthur W.
“So great salvation. Salvation from sin and from hell. It is called great because. (1.) its author is great. This is perhaps the main idea in this passage. It “began to be spoken by the Lord;” it had for its author the Son of God, who is so much superior to the angels; whom the angels were required to worship (ch. 1:6). (2.) It is great because it saves from great sins. It is adapted to deliver from all sins, no matter how aggravated. The salvation which redeems such sinners from eternal ruin is great. (3.) It is great because it saves from great dangers. The danger of an eternal hell besets the path of each one. The danger of an eternal hell! Deliverance from unending ruin! Surely that salvation must be great which shall save from such a doom!
(4.) The salvation itself is great in heaven. It exalts men to infinite honours, and places on their heads an eternal crown. Heaven, with all its glories is offered to us; and such an elevation to eternal honors.
(5.) It is great because it was effected by infinite displays of power, and wisdom, and love. It was procured by the incarnation and humiliation of the Son of God. It was accomplished amidst great sufferings and self-denials. It was attended with great miracles.” Barnes, Albert, Frew, Robert