Rakshasa wrote:Is moral discipline and keeping precepts the central teachings of the Buddha?
According to most texts, schools, and teachers, it is the root of attainments. So if by "central", you mean "basis" then yes.
Rakshasa wrote:Most of the things that we consider more "profound" explanation about the mind, body, consciousness etc actually comes from commentators like the composers of Abhidhamma with the detailed theories of the mind and dhammas or the 8 consciousnesses of Yogachara Sastra etc. And it is likely that these explanations come from their own experiences and not directly from the Buddha.
All of their teachings are based on Buddha's teachings. Anatman and so forth. For example, Nagarjuna repeatedly praises the Buddha is his texts, and considered himself to be clarifying and explaining the Buddha's teachings. Not inventing anything new.
Furthermore, Nagarjuna considered love and compassion superior to wisdom. I can provide quotes and citations if you like.
Rakshasa wrote:1. So the most essential teaching of the (historical) Buddha was morality as was the case with Jesus and Muhammad who had their own ideas about moral codes and discipline?
No, see above.
Rakshasa wrote:2. Are the Sutras/Suttas enough for a Buddhist (lay or monk) to practice Buddhism? Frankly, the Sutras are usually not understandable for most and I think they aren't meant to be intellectually understood either.
In theory yes. In practice no. The Sutras are the basis, the commentaries and treatises are to explain their intent.
"The words of the Conqueror, the precious collections of Sutra and Tantra, are the supreme instructions. [students may need the commentaries and personal instructions to understand the intent of the classic texts] Therefore, for something to be a pure personal instruction, it must bestow certain knowledge of the classic texts. [...] Know also that you accumulate the karmic obstrution of abandoning the teaching when you see those classic texts as objects of contempt and say, "Those are merely for promoting one's superficial knowledge and eliminating others' misconceptions; they do not teach the deep meaning".""
-Lam Rim Chen Mo eng v01 pg 50-51 tib 16-17
Rakshasa wrote:The only Buddhist scriptures attributed to Buddha that I found precise and clear for a meditation practitioner - like a meditation manual - are the Anapanasati Sutta and the Satipathhana Sutta, both of which deal with two forms of meditation (Shamatha and Mindfulness).
Yet most Pali Sutras teach Anatman, the crown jewel of the Buddha's teachings. That's more important. You can learn meditation from people. Learning Anatman from other people doesn't always work so well.
Rakshasa wrote:I know that maintaining precepts by itself is a herculean task for most people in this age, so it is a pretty tough practice by itself. But there should have been some Mahayana Sutra laying down the methods of practical meditation also.
The precepts for not divine law. They are guidelines to help your practice. They're good for you. Once the reason behind them is found and the benefit understood, they become easier to follow.
"Neu-sur-ba said: You must see any affliction as an enemy and attack it as soon as it arises in your mind. Otherwise, if you acquiesce when it first appears, and then nurture it with improper thoughts, you will have no way to defeat it, and it will conquer you in the end.”
-Lam Rim Chen Mo eng v01 pg. 348 tib pg. 275