法華論疏 2.97

2.97

如經「諸佛智慧甚深無量，其智慧門難見難覺難知難解難入，一切聲聞、辟支佛等所不能知」故。

As the sūtra [says]: "The wisdom of the Buddhas is profoundly deep and measureless; its gate of wisdom is difficult to see, difficult to awaken to, difficult to know, difficult to understand, and difficult to enter, unable to be known by any of the śrāvakas or pratyekabuddhas."