Hardly false.
His earliest relevant attributed variant of quote on the matter
“Sell not virtue to purchase wealth, nor Liberty to purchase power.” Poor Richard’s Almanack (1738)
Full quote in context
In fine, we have the most sensible Concern for the poor distressed Inhabitants of the Frontiers. We have taken every Step in our Power, consistent with the just Rights of the Freemen of Pennsylvania, for their Relief, and we have Reason to believe, that in the Midst of their Distresses they themselves do not wish us to go farther. Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety. Such as were inclined to defend themselves, but unable to purchase Arms and Ammunition, have, as we are informed, been supplied with both, as far as Arms could be procured, out of Monies given by the last Assembly for the King’s Use; and the large Supply of Money offered by this Bill, might enable the Governor to do every Thing else that should be judged necessary for their farther Security, if he shall think fit to accept it. Whether he could, as he supposes, “if his Hands had been properly strengthened, have put the Province into such a Posture of Defence, as might have prevented the present Mischiefs,” seems to us uncertain; since late Experience in our neighbouring Colony of Virginia (which had every Advantage for that Purpose that could be desired) shows clearly, that it is next to impossible to guard effectually an extended Frontier, settled by scattered single Families at two or three Miles Distance, so as to secure them from the insiduous Attacks of small Parties of skulking Murderers: But thus much is certain, that by refusing our Bills from Time to Time, by which great Sums were seasonably offered, he has rejected all the Strength that Money could afford him; and if his Hands are still weak or unable, he ought only to blame himself, or those who have tied them.
Original quote from Benjamin Franklin, “Pennsylvania Assembly: Reply to the Governor”, November 11, 1755;
Modified quote shows up four years later
They that can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety.
Benjamin Franklin, Historical Review of Pennsylvania (1759)
Franklin was pleading to get funds, guns and equipment so the Colonie could create it’s own security instead of relying on the Kings direction which wasn’t working.