Hi Tobias,
What I had written (the latter part of what you quoted) was not fully correct. I just revised that as follows:
When one does punna kamma, it is the avijja cetasika that is involved. However, if one has comprehended Tilakkhana FULLY (i.e., if one is an Arahant), it becomes a punna kiriya, without kammic consequences.
Now, to the question that you raised:
“Avijja is not a cetasika, moha is. Anyway, how can one do punna kamma with avijja, when this good act involves sobhana cetasika? Are the citta vithi mixed: sobhana/asobhana citta vithi?”
Yes. This is a key point that is a bit hard to grasp.
– As long as one does not FULLY understand the Four Noble Truths (or Tilakkhana), one is unable to FULLY REALIZE the unfruitful-ness AND danger in remaining in the rebirth process. So, any “good deed” (punna kamma) that one does, has at least a subtle expectation for a “good return”.
– That “expectation for a good return” reduces as one advance to higher stages of magga phala.
– For example, an Anagami does not have any expectations associated with kama loka. But still wants to live and still likes to hear/discuss Dhamma, for example.
– All future expectations for anything in this world go away only at the Arahant stage. Then any “good deed” WILL NOT have any kammic consequences. It just becomes a “good action” or punna kiriya.
This is explained in the “Kukkuravatika Sutta (Majjhima Nikāya 57) – Kammakkhaya”
– See #12 specifically.
I will get to this point slowly in the new series, “Origin of Life”
– That series is a systematic way to look at the whole process.
– In particular, the sub-section: “Worldview of the Buddha”
Anyway, please feel to ask questions. This is a key issue.