# They will certainly glean the remnant of Israel like a vineyard

"After destroying Israel, they will certainly come back to attack the people who are still alive"

# They will certainly

This refers to the enemy that Yahweh sends to destroy Israel.

# Reach out again with your hand to pick grapes from the vines

"Like people who reach out again to pick grapes from vines that they have already harvested, come back and attack the people who remain"