When you totally rest, your mind stops differentiating. You realize the world as one and you feel it is actually pretty good to feel that way (I mean you have the peace).
Life is moving very quickly. Follow the flow. Then there is peace.
When you move, you stay with one. When you don’t stay with one, there is karma. To go into more details here, when you cannot stay with one, there is a self that is separated out and you start doing things catering to the interest of that separated self (thus the so called self-generated activities), then there is karma, which means you will have to make more efforts to make up for it. So it is better to just stay with one.