Can Christians be removed from the Book of Life?

 

"You have a few names even in Sardis who have not defiled their garments; and they shall walk with Me in white, for they are worthy. He who overcomes shall be clothed in white garments, and I will not blot out his name from the Book of Life; but I will confess his name before My Father and before His angels." Revelation 3:4‭-‬5

Is salvation conditional? 

How do you overcome? 

What prevents a person from overcoming? 

Resources: 

https://96tolife.blogspot.com/search?q=Overcome&m=1

https://www.livinggodministries.net/living_god_ministries/radio_archive/always_saved.htm