He may very well be correct, even if he doesn't know what he is saying (or because he doesn't know what he is saying)
Matthew 24:31 And he shall send his angels with a great sound of a trumpet, and they shall gather together his elect* from the four winds, from one end of heaven to the other.
1588 eklektos {ek-lek-tos'}
from 1586; TDNT - 4:181,505; adj
AV - elect 16, chosen 7; 23
1) picked out, chosen
1a) chosen by God,
1a1) to obtain salvation through Christ
1a1a) Christians are called "chosen or elect" of God
1a2) the Messiah in called "elect", as appointed by God to the
most exalted office conceivable
1a3) choice, select, i.e. the best of its kind or class,
excellence preeminent: applied to certain individual
Christians
Oops.
You're not saying that the left-behind people may be themselves left behind are you? ;-)