The matter, or subject of a covenant, is always something that falleth under deliberation; for to covenant, is an act of the will; that is to say, an act, and the last act of deliberation; and is therefore always understood to be something to come; and which is judged possible for him that covenanteth, to perform. And therefore, to promise that which is known to be impossible, is no covenant. But if that prove impossible afterwards, which before was thought possible, the covenant is valid, and bindeth, though not to the thing itself, yet to the value; or, if that also be impossible, to the unfeigned endeavour of performing as much as is possible: for to more no man can be obliged. [Sidenote: Covenants how made void.] Men are freed of their covenants two ways; by performing; or by being forgiven. For performance, is the natural end of obligation; and forgiveness, the restitution of liberty; as being a retransferring of that right, in which the obligation consisted. [Sidenote: Covenants extorted by fear are valid.] Covenants entered into by fear, in the condition of mere nature, are obligatory. For example, if I covenant to pay a ransom, or service for my life, to an enemy; I am bound by it: for it is a contract, wherein one receiveth the benefit of life; the other is to receive money, or service for it; and consequently, where no other law, as in the condition of mere nature, forbiddeth the performance, the covenant is valid. Therefore prisoners of war, if trusted with the payment of their ransom, are obliged to pay it: and if a weaker prince, make a disadvantageous peace with a stronger, for fear; he is bound to keep it; unless, as hath been said before, there ariseth some new, and just cause of fear, to renew the war. And even in commonwealths, if I be forced to redeem myself from a thief by promising him money, I am bound to pay it, till the civil law discharge me. For whatsoever I may lawfully do without obligation, the same I may lawfully covenant to do through fear: and what I lawfully covenant, I cannot lawfully break. [Sidenote: The former covenant to one, makes void the later to another.] A former covenant, makes void a later. For a man that hath passed away his right to one man to-day, hath it not to pass to-morrow to another: and therefore the later promise passeth no right, but is null. [Sidenote: A man’s covenant not to defend himself is void.]