But that’s correct Cronos...not everyone who claims Christ are His. Remember Judas?.... Besides you need to read the whole article which clarifies that statement very well.
2 Peter 1:10. Wherefore the rather, brethren, give diligence to make your calling and election sure: for if ye do these things, ye shall never fall. John 10:28-29. And I give unto them eternal life; and they shall never perish, neither shall any man pluck them out of my hand. My Father, which gave them me, is greater than all; and no man is able to pluck them out of my Father's hand. 1 John 3:9. Whosoever is born of God doth not commit sin; for his seed remaineth in him: and he cannot sin, because he is born of God. 1 Peter 1:5, 9. Who are kept by the power of God through faith unto salvation ready to be revealed in the last time.... Receiving the end of your faith, even the salvation of your souls. Philippians 1:6. Being confident of this very thing, that he which hath begun a good work in you will perform it until the day of Jesus Christ.