Buddha in Pali Canon: too much thinking (even skillful) causes stress

[Tad]

MN19 is a very interesting and often overlooked sutta. It contains a few good lessons:

1) Skillful thinking is better than unskillful thinking.
2) Whatever thoughts we purse, that becomes the inclination of the mind.
3) Too much thinking, including skillful thinking, disturbs the mind and samadhi is not possible.

I think the key take away is that there are times when we have to think and cultivate skillful thinking. But then there are times to let go of both skillful and unskillful thinking. So teachers who only teach vipassana stuff, but no samatha meditation are not following what Buddha taught. I think this is very much in line with GWV.

Here is the key paragraph from the sutta. This time Sujato had the best translation.

"Then, as I meditated—diligent, keen, and resolute—a thought of renunciation arose. I understood: ‘This thought of renunciation has arisen in me. It doesn’t lead to hurting myself, hurting others, or hurting both. It nourishes wisdom, it’s on the side of freedom from anguish, and it leads to extinguishment.’ If I were to keep on thinking and considering this all night … all day … all night and day, I see no danger that would come from that. Still, thinking and considering for too long would tire my body. And when the body is tired, the mind is stressed. And when the mind is stressed, it’s far from immersion. So I stilled, settled, unified, and immersed my mind internally. Why is that? So that my mind would not be stressed."

Full sutta: https://suttacentral.net/mn19/en/sujato?layout=plain&reference=none&notes=asterisk&highlight=false&script=latin

[Jhanananda]

I think, Tad, your conclusion is excellent.  We need critical thinking to direct us on our path of mysticism, but too much thinking only distracts us from the still mind which is the doorway to samadhi (emersion).