There are many untitled “Sdstras” which are quoted in the Abhidharmadipa, which I will abbreviate here as ≪ADV≫. Needless to say, we can understand what the author of the ADV stands upon by checking these quoted texts.
There are over 40 examples where Vasubandhu, the author of Abhidharmakosabhasya (AKBh), used “Sastra” in his text. Of these examples, the title of the Prakarana-sastra and the Jñana prasthana are known as the most common. On the other hand, “Sastra” is used in 20 sentences in the ADV. Of these, three refer to texts that are non-Buddhist, and the other 17 examples seem to be quoted from some of the so-called Six pada-sastras.
I have tried to check the standpoint of the dipakara, the author of the ADV, by researching these quoted “Sastras”. Basically, the dipakara specifically mentions the title of “Sastra” only in reference to the Prajñapti-bhasya, Prakarana-sastra and the Jñana-prasthana. I could not find the titles of Dhatukaya and Vijñana-kaya mentioned anywhere, but I was able to identify sentences quoted from the Abhidharmâvatara, the Prakarana-sastra, the Samgiti-paryaya, the Dharma-skandha, the Jñana-prasthana, the Mahavibhasa, the AKBh, the Nyayanusara and the Samayapradipika by researching the use of the word of sastra. The dipakara even adopted the opinion of the AKBh when the latter represented the correct doctrine of the Sarvastivadin school.
AKBh refers to “Mahavibhasa” as simply “Vibhasa”, and the masters mentioned there by the term “vaibhasika”. The ADV, however, refers to the same text as “Vaibhasa”. It is not clear why ADV uses this form.
There are two possibilities why ADV uses the form “Vaibhasa”:
1) “Vaibhasa” comes from the rule of the Sanskrit grammar which states that when a noun changes its vowel to vrddhi form, it means “that which belongs to or is affiliated with the original noun.” In this case it means texts which belong to “Vibhasa.”
2) ADV intentionally changed the word used by the dipakara's rival, Vasubandhu, because the dipakara hated him. In fact, the dipakara created many original expressions from words previously used in the AKBh.
I would like to suggest that the most likely possibility is the first. This would mean simply texts belonging to the Sarvastivadin School, because it is difficult to believe that the dipakara changed the title of the original text.
The major difference between the ADV and the AKBh is that the dipakara uses texts of the Madhyamika and Yogacaya schools to criticise Mahayana Buddhism.