The last verse of the chapter, which is not part of the song, follows chronologically after Judges 4:24. So why does the author bother to interrupt the flow of the narrative with this lengthy song? Block explains as follows: This poem recognizes that Israel was rescued from her enemies by extraordinarily courageous and gifted individuals. But more important, if the nation ever triumphs over her enemies, the glory must go ultimately and primarily to Yahweh, who deals with his people in mercy and grace, not according to what they deserve.
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1 Then sang Deborah and Barak the son of Abinoam on that day: