Improved Selections

[@B.B.Digital_Forest]

I've only recently come across this issue: is it possible to resize a selection shape without affecting the active layer? I've been trying to airbrush light rays piercing through dark clouds. But I want to resize the 'mask' and move them around to paint more variety in the rays. However, after my initial painting any attempt to move or resize the 'mask' ends up moving the work within.