Can I have a Sutta reference for this?
Yes; it's in more than one sutta, e.g. at the end of the Anuradha Sutta (SN 22.86):
Both formerly & now, it is only stress that I describe, and the cessation of stress.
There's this commentary in footnote 14 of MN 22
(because it's also mentioned in MN 22):
Some have suggested, citing SN 12.15, that this passage means that there are only two things happening in reality: stress and the cessation of stress. However, in the context of SN 22.86, where this statement also occurs, it clearly means simply that the Buddha is selective in the topics he chooses to address. In that discourse, he is refusing to take a stand on questions regarding the ontological status of the Tathagata after death. Here he is refusing to take a stand on the related question of the status of the "existing being" (see note 13). In every case, the Buddha chooses to take a stand only on questions where the process of answering would be conducive to Awakening. On this point, see MN 63 and SN 56.31.
In other words "stress and the cessation of stress" is the only topic that the Buddha intends to "take a stand on" (conversely, at other times the Buddha is described as "trackless").
Why did he only specify two?
I think that "stress and the cessation of stress" is a summary: the four noble truths are detailed in a different sutta (SN 56.11).
Also this sutta (SN 22.86) says something slightly different about stress and cessation: e.g. it says that "that which is inconstant is stressful", that the five skandhas are stressful... and that it's good not to regard these as "self" (i.e. the anatta doctrine); good not to regard the skandhas as the Tathagata; and improper to "pin down" (make declarations about) the Tathagata existing, not existing, both, or neither.
So this sutta does talk about stress and cessation.
The whole suttas starts with, is the Tathagata described as:
- Both (existing and not-existing)
- Neither (existing nor not-existing)
- Other (none of the above)
Anuradha doesn't give a good answer, and wants to learn how to answer the question:
If I am questioned again by those wandering sectarians, how will I answer in such a way that will I speak in line with what the Blessed One has said, will not misrepresent the Blessed One with what is unfactual, will answer in line with the Dhamma, so that no one whose thinking is in line with the Dhamma will have grounds for criticizing me?
And "describing stress and the cessation of stress" is the answer or conclusion to that question.