This question came up in the Online 10-day Retreat Nov 3, 2020, guided by Delson Armstrong. Day 2 was part of a daily 30 -minute discussion on the suttas, the Dhamma talk and reflections.
Slightly edited to improve readability
I’ll break it up into a couple of things. When I was mentioning yesterday about moving, I was talking about number one; intentionally moving out of Restlessness, or intentionally moving because the body feels like it needs to move, when it’s not necessary to move.
Secondly, when it comes to where you open up your eyes; if you’re doing it because it’s just a process. In some cases, when somebody is in Infinite Consciousness, the eyes might just open up. Or, if they’re experiencing lots of joy in the sixth jhana, the eyes might just open up. That just happens as an automatic reflexive process. So, it’s not necessarily coming from your intention to open the eyes.
But in relation to what I was telling earlier about the smile, I’m referring more to seeing, and using, the smile to the extent that you need the Joy there. It can be the internal smile, or to see if you need the smile from the physical level, to bring up that Joy. But that I would not consider to be a physical movement, as compared to something like moving your limbs, or moving your posture, or something like that. Remember, when you’re doing the 6R process, there is still the movement of the mouth, there is still the movement of the lips, in order to come to the smile. To that extent you can move, if you need to smile, but beyond that you don’t want to move intentionally.