Lama Ole’s answer:
Our actions, thoughts, and words from former lives—our karma—work like a kind of glue, like something that makes things crystallize out of the possibilities of space. We then find parents when they make love—we tether ourselves to the fertilized egg and are born. And what binds us here is cause and effect and our ignorance in thinking that we are limited. We are bound here because the conditions are there, because a hook and a ring came together, because we aren’t able to see mind as clear light but instead identify with the body.
If we think we are our body, we are deluding ourselves. Rather, we have a body. The body is something through which we can work, but our true nature is clear light. As long as this is not recognized, we believe that we are our body and experience old age, sickness, death, and all the difficulties that go along with these concepts. Buddha shows us the experience that we really are clear light. This is the goal. The body is our tool to use for the benefit of all—without experiencing ups and downs, without expectations and fears, but simply because it feels so right.