四分律行事鈔資持記 1.87

1.87

檢閱中。傳聞者，或章疏所出，或口相傳授，容有舛誤，不可輒憑；故皆親檢，使後無疑。

Under "Examining [the Sources]": "Passed down by report" refers either to what appears in commentaries and subcommentaries or to what has been transmitted orally from person to person. Because errors may easily occur, these cannot be relied upon hastily. Therefore, he personally examined them all so that later generations would have no doubts.