金光明最勝王經疏 4.28

4.28

下徵及釋也。徵者可知。釋中，初釋不可得不可說之所以，以菩提義及菩提心同依真如無能說得，離計執故。

Below are the query and the explanation. The query is clear. In the explanation, it first explains the reason why they cannot be apprehended or spoken of: because the meaning of bodhi and the bodhicitta alike rely upon tathatā, there is nothing that can be spoken of or attained, as they are free from conceptual grasping.