“Oh, how I love that doctrine of the perseverance of the saints!” So said Spurgeon in regards to this final of the five points of Calvinism.
This is the sixth article in the series “C.H. Spurgeon on the Doctrines of Grace,” which discusses Spurgeon’s views on Calvinism as seen in his preaching and writing.
The doctrine known as the perseverance of the saints teaches that those who truly place their faith in Christ cannot lose their salvation. You may have heard this referred to as ‘once saved, always saved.’
C.H. Spurgeon said that if he were unable to preach this important doctrine he would “at once renounce the pulpit.” 
The forgiven sinner has a justification that is sure, and every sin—not only transgressions made prior to conversion—is forgiven by God’s grace. So passionate was Spurgeon on the truth of this doctrine that he wrote:
If one dear saint of God had perished, so might all; if one of the covenant ones be lost, so may all be; and then there is no Gospel promise true, but the Bible is a lie, and there is nothing in it worth my acceptance. I will be an infidel at once when I can believe that a saint of God can ever fall finally. If God hath loved me once, then He will love me forever. 
The perseverance of the saints reflects the Scripture’s teaching that salvation cannot be lost (John 5:27; John 10:28). Those who are among God’s elect will surely see eternal life.
Spurgeon flatly rejected the possibility of “a Gospel which lets saints fall away after they are called.”  To him, this would be no Gospel at all:
I could never either believe or preach a gospel which saves me today and rejects me tomorrow,-a gospel which puts me in Christ’s family one hour, and makes me a child of the devil the next,-a gospel which first justified and then condemns me,-a gospel which pardons me, and afterwards casts me down to hell. Such a gospel is abhorrent to reason itself, much more is it contrary to the mind of the God whom we delight to serve. 
Spurgeon called the doctrine of the perseverance of the saints one of the Bible’s “crowning attractions” and he held tightly to Jesus’ words in John 10:28:
“I give them eternal life, and they will never perish, and no one will snatch them out of my hand.”
Articles exploring Spurgeon’s words regarding each of the Doctrines of Grace:
For a more detailed look at the Perseverance of the Saints, please see The Five Points of Calvinism – Defining the Doctrines of Grace
 Eric W. Hayden, Searchlight on Spurgeon: Spurgeon Speaks for Himself, (Pilgrim Publications, 1973), 81.
 C.H. Spurgeon and David Otis Fuller, C.H. Spurgeon’s Autobiography, (Zondervan Pub. House, 1946), 52.
 Searchlight on Spurgeon: Spurgeon Speaks for Himself, 81.