No, this statement does not hold up under scrutiny from Scripture or church history. It is too absolute and risks misdiagnosing genuine believers who are in a season of doubt or struggle. Scripture and the experience of many of the most devoted, fruitful Christians in history show that a true regenerate person can battle deep doubt about their salvation without that doubt proving they “haven’t been” saved.
Complete rubbish.
3 of the 4 gospels were firsthand eyewitnesses
Luke wrote his book based on his own investigation and interviews of eyewitnesses for the sake of the Greeks
Jesus appeared to more than 500 people after his resurrection over 50 days.