There is a never ending argument between the two most popular theological viewpoints in protestant theology on the matter of perseverance. Calvinists believe that all who were chosen by Christ persevere because God causes them to do so. Armenianists believe that man has to persevere in order to be a Christian and retain their salvation. 
Where there are logical arguments for both, I believe that scripture points to a middle ground.
CALVINISM
Calvinism says that you are chosen for salvation before time began. Because of this, there is nothing that can be done to lose your salvation. They believe that the person who lacks perseverance in faith and falls away was never truly saved in the first place.
ARMENIANISM
The Armenian tradition says that no one is chosen, that you have to choose Christ. They believe in complete free will. Because of this, the person who lacks perseverance can actually fall away from Christ, thereby losing their salvation. In the same way that one chooses to follow Christ, resulting in salvation, they can choose to later deny Christ and lose their salvation.
MY POINT OF VIEW
There is a lot of scripture to back up both of these arguments on perseverance. I believe that scripture actually provides a middle ground. Romans 8 says, “For those God foreknew he also predestined to be conformed to the likeness of his Son” (v. 29). I believe that this verse implies God’s foreknowledge of who would choose Him; that His eternal plan was for the sanctification (conformity to the likeness of Christ) of those who would choose to follow—freewill as opposed to predestination. This view opposes Calvinism.
I do not believe that someone can fall away, once saved, regardless of what we do. Salvation is God’s to give and He said, “Never will I leave you; never will I forsake you” (Hebrews 13.5). This view opposes Armenianism. At the same time, however, I do believe that there are many Christians who will fall away, although I believe it is most likely that Calvinists and Armenianists are both correct; some were likely never saved and others are saved, but have simply become too entangled by the cares and worries of the world to remain faithful.
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