Thanks for your very helpful reply to my question. I especially
appreciated the quotation from the Paraayana towards the end, as this
makes clearer to me the meaning of saddhaa in the Upanisa Sutta - that
it is connected to understanding of dukkha and to mindfulness.
However, you did not give any references to the lokuttara cittas that
I asked about. Is this more of an Abhidhamma concept I wonder?