As the preceding units.
The verb הפך (hpk) usually implies a surprising change. Here the change is certainly shocking. For Adonai claims to have overturned "some of you" as when God (אֱלֹהִים) overthrew "Sodom and Gomorrah".
The image of "a smoldering stick pulled from fire" is found also in Zech 3:2 so either it is a regular image - which happens not to be used elsewhere in the Bible - or it was memorable enough to be borrowed by Zechariah (as later by John Wesley). In either case it is one of Amos' contributions to the English language - or at least the language of Evangelical Christians. It is a good picture of something totally useless - except to continue burning - unless it is worked on so as to change it and cut away the "bad" and leave wood from which something can be made.
This page is part of the Hypertext Bible Commentary - Amos,
© Tim Bulkeley, 1996-2005, Tim Bulkeley. All rights reserved.