The truth is in plain sight. Those who perish, Revelation 20:15, "And whosoever was not found written in the book of life was cast into the lake of fire."
Jesus taught, Mark 10:14, "Allow the little children to come unto me, and forbid them not: for of such is the kingdom of God." And in Matthew 18:3, "Verily I say unto you, Except ye be converted, and become as little children, ye shall not enter into the kingdom of heaven." And to Nicodemus, John 3:3, "Verily, verily, I say unto thee, Except a man be born again, he cannot see the kingdom of God." To which Nicodemus asked, "How can a man be born when he is old? can he enter the second time into his mother's womb, and be born?" Then Jesus exlained.
Now John wrote, 1 John 5:4, "For whatsoever is born of God overcometh the world: and this is the victory that overcometh the world, even our faith." And one of the promises, Revelation 3:5, "He that overcometh, . . . I will not blot out his name out of the book of life, . . ."
The interpreation being that all names begin in God's book, so the reason Christ died for many being the whole world, is so names can be kept in the book, 1 John 2:2. Nowhere in the word of God does it speak of names being added to the book, but being removed do to sin, Exodus 32;33, Psalms 69:27-28. Little children are safe because for whom Christ died. We must again become children to God.