Joel 2:6 - Ellicott's Commentary On The Whole Bible

All faces shall gather blackness. — There are different explanations of this Hebrew phrase, which expresses the result of terror. Some translate it “withdraw their ruddiness,” i.e., grow pale; others, “draw into themselves their colour;” others, “contract a livid character.” The alternative rendering in the margin, “pot,” which is that of the LXX., the Vulg., and of Luther’s translation, is obtained from the similarity of the Hebrew words for “ruddiness” and “pot.” The comparison is in this case between the faces growing black under the influence of fear, and of pots under the action of fire. The prophet Nahum uses the same expression (Joel 2:10).