Jesus continues to tell his disciples what will happen before he comes again.

## Then ##

When the Son of Man comes.

## one will be taken, and one will be left behind. ##

Possible meanings: 1) God will take one away to heaven and will leave the other on earth for punishment (see UDB) or 2) the angels will take one away for punishment and leave the other for blessing (see [Matthew 13:40](../13/40.md)).

## mill ##

a tool for grinding

## Therefore ##

"Because of what I have told you"

## be on your guard ##

"pay attention"