Jiujing jijie 九經集解 "Collected explanations to the Nine Classics", also called Jie'an jingshuo 介庵經說 "Explanations to the Classics by the Jie'an Studio" is a collection of commentaries on the Confucian Classics compiled during the Qing period 清 (1644-1911) by Lei Xueqi 雷學淇 (early 19th cent.), courtesy name Zhanshu 瞻叔, style Zhuqing 竹卿 or Jie'an 介庵. He hailed from Tongzhou 通州 (modern Tongxian 通縣, Hebei) and obtained his jinshi degree in 1814. Lei made a career as magistrate (zhixian 知縣) of Heshuo 和順 in Shanxi, then of Yongcong 永從 in Guizhou, but then returned home to care for his parents.
All his life Lei Xueqi was highly interested in the Confucian Classics and their interpretations and collected all explanations and commentaries he was able to obtain. The main aim of his research was to bring the various commentaries (like zhuan 傳, jian 箋, zhu 注 or shu 疏) into one line, and to compare them critically, but also, to point at the differences between interlineary commentaries with general comments to "the meaning" of one book or a group of texts. Apart from the Jiujing jijie, Lei Xuqi wrote the books Zhushu jinian kao 竹書紀年考, Jinian yizheng 紀年義證, Xia xiaozheng jingzhuan kao 夏小正經傳考, Xia xiaozheng benyi 夏小正本義, Yi'ao'aozhai jingyi kao 亦囂囂齋經義考 and Gujin tianxiang kao 古今天象考.
The 9-juan long Jiujing jijie includes commentaries on nine Confucian Classics, namely the Yijing 易經 (Zhouyi 周易), Shangshu 書經, Shijing 詩經 (Maoshi 毛詩), Zhouli 周禮, Yili 禮記, Chunqiu 春秋, Lunyu 論語, Mengzi 孟子 and the gloss book Erya 爾雅. There are also three paragraphs to the classic Xiaojing 孝經 positioned just before the Erya, but not with a separate headline.
Lei Xueqi was able to demonstrate that the Han-period 漢 (206 BCE-220 CE) scholar Fei Zhi 費直 had written zhangju 章句 sentence-by-sentence commentaries on the Yijing, and had not been the creator of the tuan 彖 and xiang 象 commentaries. Lei identified the Shang dynasty 商 (17th-11th cent. BCE) capital Yin 殷 with Anyang 安陽 and the earlier capital Bo 亳 with Shangqiu 商丘. This contradicted some statements assuming that there were two places called Yin and two places called Bo. He proved that ivory and a jade type called ji 璣 were only used for tools from the Eastern Han period 東漢 (25-220 CE) on, and not earlier, as mentioned in the chapter Yaodian 堯典 of the Shangshu.
According to his findings, the kings of the Zhou dynasty 周 (11th cent.-221 BCE) had seven ancestral altars, but the Shang kings only five. The statements in the Xiaojing about the female quarters (guimen 閨門) must be interpolations of a later time. He was furthermore able to demonstrate that Confucius had not revised and edited the Shijing "Book of Songs", as often said. Lei Xueqi also touched on a wide range of various topics, like sacrificial procedures, settlement and field sytems, military logistics, the five sacred mountains (wuyue 五岳), court robes, and the life times of the philosopher Mengzi 孟子 (Meng Ke 孟軻).
The merits of Lei Xueqi are to important that Zhang Zhidong 張之洞 (1837-1909) said that he must be added to the great Confucian scholars of the Han and Song 宋 (960-1279) periods and that he surpassed his contemporarian Weng Fanggang 翁方綱 (1733-1818).