If we could but once believe the teaching that the child of God might fall from grace and perish everlastingly, we might, indeed, shut our Bible in despair. To what purpose would my preaching be–the preaching of a rickety gospel like that? To what purpose your faith be–a faith in a God that cannot and would not carry on to the end? To what use the blood of Christ, if it were shed in vain, and did not bring the blood-bought ones securely home? To what purpose the Spirit, if he were not omnipotent enough to overcome our wandering, to arrest our sins and make us perfect, and present us faultless before the throne of God at last? The doctrine of the final perseverance of the saints is, I believe, as thoroughly bound up with the standing or falling of the gospel, as is the article of justification by faith. Give that up and I see no gospel left; I see no beauty in religion that is worthy of my acceptance or that deserves my admiration.
An unchanging God, an everlasting covenant, a sure mercy–these are the things that my soul delights in, and I know your hearts love to feed upon them. But take these away, and what have we? We have a foundation of wood, hay, straw, and stubble. We have nothing solid. We have a fort of earthworks, a mud hovel through which the thief may break and steal away our treasures. No, this foundation stands sure–“The Lord knows them that are his” and he will certainly bring them all to his right hand at last in glory everlasting.
– C. H. Spurgeon