Jefferson was immediately reworking George Mason, whose premable to the proposed Virginia constitution, adopted June 12, 1776, says, “All men are created equally free and independent and have certain inherent and natural rights…, among which are the enjoyment of life and liberty, with the means of acquiring and possessing property, and pursuing and obtaining happiness and safety.”
Two points.
1. These are stock phrases of English whiggery: Locke, Kames, Jim Bob Jones, everybody used them.
2. Jefferson’s genius was to phrase it absolutely right. Compare poor old Mason floundering around with what Jefferson wrought. As Mark Twain said, the difference between the right word and the almost right word is the difference between lightning and lightning bug.