The title of this post is part of a quote from DN 15, the Mahānidānasutta. It is the beginning of the Buddha’s remonstration of Ānanda for his lack of appreciation of the profundity of dependent origination. Though I believe many here are probably familiar with the episode, if not the quote. In fact, I feel more people know about the episode than know about anything else pertaining to the sutta.
I posted on D&D a few months back (here) on an Ekottarikāgama partial parallel to DN 15 built around an expansion of this episode into a sort of jātaka story which depicted the Buddha and Ānanda as father and young son deities with Ānanda nearly drowning in the ocean because of having misread its depth and having to be rescued by the Buddha.
In the DN 15 commentary, the original episode (appearing alongside illustrative parables which echo the EĀ story, comparing the depth of DO to deep water in which only giant, supernatural beings can wade) is greatly expanded.
All of this got me thinking, and I wanted to ask if anyone more familiar than I with commentarial, abhidhammic/abhidharmic and such literature (early or medieval) might know of other places where this episode is recounted, highlighted, analyzed, etc.