《后汉书·列传·郎顗襄楷列传下》
所以《经》说： 雷以动之，雨以润之。 
故《经》曰： 雷以动之，雨以润之。 
Therefore, the Scripture says: Thunder moves it, and rain moistens it.
<s>[INST] Identify the key themes in this Classical Chinese text and explain them in English: 故《经》曰： 雷以动之，雨以润之。  [/INST] Therefore, the Scripture says: Thunder moves it, and rain moistens it.</s>
Identify the key themes in this Classical Chinese text and explain them in English: 故《经》曰： 雷以动之，雨以润之。
user
Therefore, the Scripture says: Thunder moves it, and rain moistens it.
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