"Did the Buddha really teach these anantarika-karma (heinous crimes) for Buddhists?"
https://en.wikipedia.org/wiki/Filial_piety_in_BuddhismBut in a more recent development, starting with Buddhist studies scholars such as John Strong and Gregory Schopen, it has been shown that filial piety was part of Buddhist teaching since early times, though Strong did regard it as a compromise to Brahmanical ethics.[43][44]
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At the time when Buddhism developed in India, there was criticism that Buddhist otherworldly ideals did not fit in with expectations of filial piety. Devotion to the mother was seen as a fundamental virtue, and early Buddhists had to reconcile Buddhist doctrine and practice with Indian social institutions.[46][47]
I agree with this interpretation. The origin of parent-worship in India is surely Vedic tradition:
https://en.wikipedia.org/wiki/%C5%9Ar%C4%81ddhaIn contrast, the Buddhist view:
https://en.wikipedia.org/wiki/Prat%C4%ABtyasamutp%C4%81dathe first four nidanas resemble the Hymn of Creation (RigVeda X, 12) and other Vedic sources which describe the creation of the cosmos.[125][6] Jurewicz argues that dependent origination is "a polemic" against the Vedic creation myth and that, paradoxically, "the Buddha extracted the essence of Vedic cosmogony and expressed in explicit language." Richard Gombrich agrees with this view, and argues that the first four elements of dependent origination are the Buddha's attempt to "ironize and criticize Vedic cosmogony."[127]
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According to Jurewicz, "in Vedic cosmogony, the act of giving a name and a form marks the final formation of the creator's atman." This may go back to the Vedic birth ceremony in which a father gives a name to his son.[6] In Vedic creation pure consciousness creates the world as name and form (nama-rupa) and then enters it. However, in this process, consciousness also hides from itself, losing sight of its real identity.[125] The Buddhist view of consciousness entering name and form depicts a similar chain of events leading to deeper ignorance and entanglement with the world.[6]
Jurewizc further argues that the rest of the twelve nidanas show similarities with the terms and ideas found in Vedic cosmogeny, especially as it relates to the sacrificial fire (as a metaphor for desire and existence). These Vedic terms may have been adopted by the Buddha to communicate his message of not-self because his audience (often educated in Vedic thought) would understand their basic meaning.[6] According to Jurewizc, dependent origination replicates the general Vedic creation model, but negates its metaphysics and its morals. Furthermore, Jurewizc argues that:[6]
This deprives the Vedic cosmogony of its positive meaning as the successful activity of the Absolute and presents it as a chain of absurd, meaningless changes which could only result in the repeated death of anyone who would reproduce this cosmogonic process in ritual activity and everyday life,
(This approach is very similar to what we do here with enemy content.)
Now from your link:
Intentionally murdering one's father.
Intentionally murdering one's mother.
Killing an Arhat (fully enlightened being).
Shedding the blood of a Buddha. This includes damaging works related to the Buddha and is not limited to harming the Buddha's person.[7]
Creating a schism (heresy) within the Sangha, the community of Buddhist monks, nuns and pariṣā who try to attain enlightenment.
Why is it that the latter three items do not specify the relation of the object to oneself, but the first two items do? If hypothetically there were a valid reason to not murder one's own father, there should be a similarly valid reason to not murder someone else's father, because nothing in Buddhist ethics is supposed to depend on the object's personal relation with the subject (considering that the very notion of identity is illusory). The way it is written, it is as though the first two items were added by Vedic traditionalist parents worried about being murdered by their Buddhist-converted offspring and trying to pre-emptively intimidate them against the idea.
There are other problems with this list. How is someone supposed to know who is an Arhat/Buddha without being one oneself? (But if one is an Arhat/Buddha oneself, one would not need to follow a list to know how to behave ethically!) Therefore it seems that the list is a device intended to benefit charlatans who want to proclaim themselves to be Arhats/Buddhas but do not want to be killed by those who suspect a scam. The last item is the most tricky. If someone in a position of authority within the Sangha tries to misdirect it, and someone else sees this happening and challenges the misdirector, it would be the latter who will appear as though they are causing a schism. All in all, this list seems like a strategic setup for Vedic traditionalists to subvert Buddhism while paralyzing the prospective resistance with fear.