《搜神记·卷十六》
温序接过剑，把胡须衔在嘴里，叹息说： 别让泥土把我的胡须搞脏了。 
序受剑，衔须着口中，叹曰： 则令须污土。 
Wen Xu took the sword, put his beard in his mouth, and sighed, "Don't let the mud dirty my beard."
<s>[INST] Kindly elucidate the central themes in this passage in English: 序受剑，衔须着口中，叹曰： 则令须污土。  [/INST] Wen Xu took the sword, put his beard in his mouth, and sighed, "Don't let the mud dirty my beard."</s>
Kindly elucidate the central themes in this passage in English: 序受剑，衔须着口中，叹曰： 则令须污土。
user
Wen Xu took the sword, put his beard in his mouth, and sighed, "Don't let the mud dirty my beard."
assistant