肇論新疏 2.377

2.377

是以須菩提終日說般若，而云無所說。此絕言之道，知何以傳？庶（希望也）參玄君子有以會之耳。

Therefore Subhūti spoke prajñā all day, yet said that nothing was spoken. As for this path where words are cut off, how could cognition transmit it? It is only hoped that gentlemen who engage the profound will grasp it.