Incest is human sexual activity between family members or close relatives. This typically includes sexual activity between people in consanguinity (blood relations), and sometimes those related by affinity (marriage or stepfamily), adoption, clan or lineage.
In some societies, such as those of Ancient Egypt, brother–sister, father–daughter, mother–son, cousin–cousin, aunt–nephew, uncle–niece, and other combinations of relations within a royal family were married as a means of perpetuating the royal lineage.
DN 3 appears to say the Sakyan Aristocrats were superior to Brahmans because the Sakyans Aristocrats slept with their blood sisters and thus keep the Aristocrat lineage pure.
Recollecting the ancient name and clan of your mother and father, the Sakyans were the children of the masters, while you’re descended from the son of a female bondservant of the Sakyans. But the Sakyans claim King Okkāka as their grandfather.
Once upon a time, King Okkāka, wishing to divert the royal succession to the son of his most beloved queen, banished the elder princes from the realm—Okkāmukha, Karakaṇḍa, Hatthinika and Sinisūra. They made their home beside a lotus pond on the slopes of the Himalayas, where there was a large teak grove. For fear of diluting their lineage, they slept with their own sisters.
Then, Ambaṭṭha, King Okkāka was inspired to exclaim: ‘The princes are indeed Sakyans! The princes are indeed the best Sakyans!’ From that day on the Sakyans were recognized, and he was their founder.
For I also say this:
"The aristocrat is best of those people who take clan as the standard. But one accomplished in knowledge and conduct is best of gods and humans.”
It was only yesterday when an acquaintance was tell me how he was part of an Australian veterinary team that went to Thailand to rectify the birth deformities of in-bred goats by impregnating the Thai goats with sperm from Australian goats.
Did the Buddha praise the practise of incest? Are there any Commentary apologetics for this above, seemingly, ignorant teaching in DN 3? I thought the Buddha was supposed to be omniscient? Or is DN 3 just another fake DN sutta composed to convert eḷamūgo to Buddhism?