"Those who would give up Essential Liberty to purchase a little Temporary Safety deserve neither Liberty nor Safety."
This is probably not the most common usage of the phrase. You might have heard this one:
"They that can give up essential liberty to obtain a little safety deserve neither liberty nor safety."
Or perhaps even:
"He who would trade liberty for some temporary security, deserves neither liberty nor security."
I found a page that details the discrepancy between the first two, and mentions that the oft-attributed writer (Benjamin Franklin) may not be the author: It might actually be Richard Jackson, with Franklin perhaps editing for effect. I suspect we will never know. But it's a good quote.