I'm not an expert, but I think that the concept of "self-ownership" is actually from a subset of libertarianism, the Propertarians. It is their beliefs that all individual liberties extend from this, original, "sacred right". A person's right to Life, to Liberty, to Pursuit of Happiness extends not from divine providence or from the government, but from the concept that, before anything else, they own themself. This concept is also applied from them in determining the boundaries and relative consequences of our actions. For example, my rights to liberty do not include the freedom to destroy my neighbor's car. If I did destroy his car, however, I'd be responsible, but not as much as if I cut off his arm. Both "belong" to him, but one is ordinary property and the other is sacred property. I tend to agree with this, and feel that no matter what a person's religious beliefs, it makes a good foundation for legal doctrine.
I'd just be happy to see the laws changed enough so that I actually have the rights of Life, of Liberty, of Pursuit of Happiness.