2 Peter 3:16-17:

As also in all his epistles, speaking in them of these things; in which are some things hard to be understood, which they that are unlearned and unstable wrest, as they do also the other scriptures, unto their own destruction.
Ye therefore, beloved, seeing ye know these things before, beware lest ye also, being led away with the error of the wicked, fall from your own stedfastness.

See also:

Objection: Healing Cannot Be in the Atonement Because Healing Can Be Lost, but Salvation Cannot Be Lost