Although this is an extremely popular view today, it is nowhere to be found in the bible, but rather, a reading of the scriptures will prove to us that just the opposite in the truth. Let’s consider some examples.
1 Timothy 4:1 “Now the Spirit expressly says that in latter times some will depart from the faith, giving heed to deceiving spirits and doctrines of demons” If I told you I departed from Los Angeles, does that statement necessitate that I was in Los Angeles? Of course! But men still refute 1 Timothy 4:1 by suggesting that those referenced in the verse were never actually in the faith. How can that be if the text specifically says that they departed from the faith? Indeed, the point of the Holy Spirit is to warn the Christians of the troubling time when people who were once saved will depart from salvation and lose their souls.
Galatians 5:4 essential states the same truth, but different wording. The point that the Galatians had “fallen from grace” is proof that they once were in the grace of God. You can’t fall from the window of a building if you never set foot in the building; likewise you can’t fall from grace if you’ve never been in the grace of God.
Revelation 3:5 “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.” This verse is the third one that we have considered under the same principle. The idea that God will not blot out one’s name from the book of Life is conditioned on whether that individual successfully overcomes sin. The result is opposite for the one who fails to overcome, their name will be blotted out. But if they were never saved to begin with, why then was their name in the book? And so for their name to be removed is teaching us that our salvation is not secure. We must continue to take the necessary steps of obedience throughout our lives in order to be saved. This is what the bible teaches; to teach otherwise will give one a false assurance of their salvation.