He bared his back and bore thorns to apologize to his friend.
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history
A thorny shrub, hence 荆棘 (thorns; figuratively, hardship). In the story behind 负荆请罪, a general carried a thorn rod on his bare back to ask forgiveness, now a byword for a sincere apology. It is also an old name for the state of Chu.
Below the grass, 刑 supplies the sound — xíng drifting to jīng. Since thorn rods were once used for punishment, the phonetic also carries a faint thematic echo. The same phonetic appears in 型.
