# By the breath of God they perish; by the blast of his anger they are consumed

The writer explains a single idea using two different statements. This is a form of Hebrew poetry used for emphasis, clarity, teaching, or all three.

# the breath of God

This may represent the action of God giving a command.

# the blast of his anger

This suggests the heavy breathing that a person sometimes does through his nose when he is very angry.

# breath ... blast

"By the puff of God's mouth they die; the rushing wind of his anger devastates them.". The second phrase builds on the first. They make the same point. 

# perish ... are consumed

"By the puff of God's breath they die, the rushing wind of his anger devastates them."

# they are consumed

Here being consumed or eaten represents being killed.