“Is it ok to practice Centering Prayer on my back?”
YES!
Some people have back and neck issues.
It can be difficult to sit and practice Centering Prayer with these issues.
Lie down if you must.
The most important thing to remember is why we practice Centering Prayer.
The purpose of Centering Prayer is to open to the presence and actions of God within.
We let God pray in us.
As long as you remain alert and use your sacred word when you engage your thoughts, you can still practice Centering Prayer whether seated or on your back.
God is delighted that you have taken the time to sit or lie.
Go ahead and practice Centering Prayer on your back if for health purposes you must.
And be okay with it.
Let me know if I can help.