Locke believed that people have the natural right to life. Jefferson included the natural right of an individual to live a safe and peaceful life.
Locke believed that freedom is a natural right and that government ought not to hinder the freedom of an individual. Jefferson included liberty to ensure that Americans have the right to freedom.
Jefferson initially wrote "property" instead of "pursuit of happiness." Locke believed that the ownership of property led to an enjoyable life. Jefferson, in the Declaration of Independence, expanded this idea by including the pursuit of the enjoyment of life.