妙法蓮華經玄義 7.57

7.57

若理事為本迹者，指事為迹，攝得本時諸麁境；指理為本，攝得本時諸妙境。最初之本為本，但本而非迹；最後已說，但迹而非本；中間亦迹亦本。若無本時之本，不能垂得中間、最後之迹；若無已說之迹，不能顯得今說之本。本迹雖殊，不思議一也。

If regarding principle and phenomena as the original source and the traces: designating phenomena as traces encompasses the various coarse realms of the original time; designating principle as the original source encompasses the various subtle realms of the original time. The initial origin is the original source, only original source and not traces; the final preaching is only traces and not the original source; the intermediate is both traces and original source. If there were no original source of the original time, it could not manifest the intermediate and final traces; if there were no traces already preached, the original source preached at present could not be revealed. Although original source and traces are distinct, they are an inconceivable unity.