The following is from Spurgeon's sermon,
"Man's Thoughts and God's Thoughts"
As for peace in the hour of death, he who is not
pardoned while living is not likely to be pardoned
when dying. Nine out of ten, perhaps nine hundred
and ninety-nine out of every thousand of professed
death-bed salvations are a delusion.
We have good facts to prove that.
A certain physician collected notes of several hundred
cases of people who professed conversion when they
thought they were dying. These people did not die
as they had expected to, but continued to live.
In the case of all but one they lived just as they had
lived before, though when they were thought to be
dying they appeared as if they were truly converted.
Do not look forward to a death-bed salvation,
it is a mere snare of Satan.
Of them the proverbs are true: "A dog returns to its
vomit," and, "A sow that is washed goes back to her
wallowing in the mud." -2 Peter 2:22