He shall not depart out of darkness - He shall not escape from calamity; see Job 15:22. He shall not be able to rise again, but shall be continually poor.
The flame shall dry up his branches - As the fire consumes the green branches of a tree, so shall punishment do to him. This comparison is very forcible, and the idea is, that the man who has been prospered as a tree shall be consumed - as the fire consumes a tree when it passes through the branches. The comparison of a prosperous man with a tree is very common, and very beautiful. Thus, the Psalmist says,
I have seen the wicked in great power,
And spreading himself like a green bay tree. Psalms 37:35.
Compare Psalms 92:12-13. The aged Skenandoah - a chief of the Oneida tribe of Indians, said,” I am an aged hemlock. The winds of an hundred winters have whistled through my branches. I am dead at the top. My branches are falling,” etc.
And by the breath of his mouth shall he go away - That is, by the breath of the mouth of God. God is not indeed specified, but it is not unusual to speak of him in this manner. The image here seems to be that of the destruction of a man by a burning wind or by lightning. As a tree is dried up, or is rent by lightning, or is torn up from the roots by a tempest sent by the Deity, so the wicked will be destroyed.