According to Hebrews:6:4-9, the “falling away” doctrine, rather than glorifying Christ, once again holds Him up to shame and ridicule before the world for two reasons: if we could lose our salvation, then 1) Christ would have to be crucified again to save us again; and 2) He would be ridiculed for dying to purchase a salvation but not making adequate provision to preserve it—for giving a priceless gift to those who would inevitably lose it. If Christ’s death in our place for our sins and His resurrection were not sufficient to keep us saved, then He has foolishly wasted His time. If we could not live a good enough life to earn salvation, it is certain we cannot live a good enough life to keep it. To make the salvation He procured ultimately dependent upon our faltering works would be the utmost folly.
“Falling away” doctrine makes us worse off after we are saved than before. At least before conversion we can get saved. But after we are saved and have lost our salvation (if we could), we can’t get saved again, but are lost forever. Hebrews:6:6 declares, “If (not when) they shall fall away…it is impossible…to renew them again unto repentance.” That “falling away” is hypothetical is clear (verse 9): “But, beloved, we are persuaded better things of you, and things that accompany salvation, though we thus speak.” So “falling away” does not “accompany salvation.” The writer is showing us that if we could lose our salvation, we could never get it back without Christ dying again upon the cross. This is folly. He would have to die an infinite number of times (that is, every time every person who was once saved sinned and was lost and wanted to be “saved again”). Thus, those who reject “once saved, always saved” can only replace it with “once lost, always lost.”
Dave Hunt, An Urgent Call to a Serious Faith”, The Berean Call,
December 2002 revision, pp. 220,221