Can you show me the Scripture on this one? I must have missed it.
The devils' lies began in Genesis 3:1, and every evil thing and lie in the Bible is of the devil; which includes the presupposition that men can lose their salvation. God is in the business of providing assurance of eternal salvation, and not providing ways in which men might lose their salvation: that evil presupposition, is a lie of the devil, to cause men and women to fear that they can lose their salvation.
That kind of thinking is prevalent in the Romans Catholic 'church' and it is a lie of the devil and is a doctrine of demons.