Word play

“Cain’s name is significant for several other reasons as well. First, while Cain’s name initially refers to the gaining, acquisition, and creation of life (see ,)4:1he ironically is responsible for the losing, taking, and destruction of life. Second, his name is quite similar to both the verb קין [qyn], which in the Polel means ‘sing a funeral song’, and its related noun קינה [qynh], which refers to a ‘dirge’. It is striking that words closely associated with death are quite similar to the name of the individual who brings death into the world. Finally, it may not be accidental that Cain’s name has a homonym used in 2 Sam 21:16 to describe one of the weapons with which Ishbi-benov intends to kill David. Although readers are never told the means by which Cain strikes down his brother (Gen 4:8), the fact that Cain’s name sounds like an instrument of death does not bode well for Abel.”—From Fratricide to Forgiveness, page 132, footnote

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The Hebrew Bible loves word-play—most of which is lost in the English translations.
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