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Study Dictionary
Vain
VAIN [ISBE]
VAIN - van: The adjective of "vanity," and representing the same Hebrew and Greek words as does the latter, with a few additions (chiefly kenos, "empty," and its compounds in the New Testament). And "vain" can always be replaced by its synonym "empty," often with advantage in modern English (Job 15:2; 1 Cor 15:14, etc.). The exception is the phrase "in vain," and even there the interchange can be made if some (understood) noun such as "ways" be added. So "to take God's name in vain" (Ex 20:7; Dt 5:11) means simply to take it for an "empty" ("not good") purpose.
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