Please provide a concrete explanation of how you and / or your denomination determine the person has been "called" by God.
How do you know for certain that they are no longer "spiritually blind"?
How do you know for certain if their sudden revelatory understanding of the Gospel of Jesus Christ is in anyway accurate?
There is no concrete explanation.
It was 6 months before I realized what had happened to me!
Years later, I was blessed to hear Billy Graham say on TV the same thing: 6 months!
FYI, we both have been born again from above with the indwelling Holy Spirit.
Every believer is spiritually blind to some extent ... no one knows everything.
When one all of a sudden one no longer considers Jesus and His Gospel as foolishness,
then one "knows" they believe ... spiritual revelation is like a light bulb going on.
Ever hear the phrase, "You know that you know that you know!"?
Problem is ... many cultists feel the same way.
Ever hear that Satan is the Great Counterfeiter?
Not to mention the greatest liar and deceiver ever!!!