13. It is a question often moved, whether such covenants oblige, as are extorted from men by fear. As for example: whether, if a man for fear of death, have promised to give a thief an hundred pounds the next day, and not discover him, whether such covenant be obligatory or not. And though in some cases such covenant may be void, yet it is not therefore void, because extorted by fear. For there appeareth no reason, why that which we do upon fear, should be less firm than that which we do for covetousness. For both the one and the other maketh the action voluntary. And if no covenant should be good, that proceedeth from fear of death, no conditions of peace between enemies, nor any laws could be of force; which are all consented to from that fear. For who would lose the liberty that nature hath given him, of governing himself by his own will and power, if they feared not death in the retaining of it? What prisoner in war might be trusted to seek his ransom, and ought not rather to be killed, if he were not tied by the grant of his life, to perform his promise? But after the introduction of policy and laws, the case may alter; for if by the law the performance of such a covenant be forbidden, then he that promiseth anything to a thief, not only may, but must refuse to perform it. But if the law forbid not the performance, but leave it to the will of the promiser, then is the performance still lawful: and the covenant of things lawful is obligatory, even towards a thief.
14. He that giveth, promiseth, or covenanteth to one, and after giveth, promiseth, or covenanteth the same to another, maketh void the latter act. For it is impossible for a man to transfer that right which he himself hath not; and that right he hath not, which he himself hath before transferred.
15. An OATH is a clause annexed to a promise, containing a renunciation of God's mercy, by him that promiseth, in case he perform not as far as is lawful and possible for him to do. And this appeareth by the words which make the essence of the oath (viz.) so help me God. So also was it amongst the heathen. And the form of the Romans was, Thou Jupiter kill him that breaketh, as I kill this beast. The intention therefore of an oath being to provoke vengeance upon the breakers of covenants; it is to no purpose to swear by men, be they never so great, because their punishment by divers accidents may be avoided, whether they will, or no; but God's punishment not. Though it were a custom of many nations, to swear by the life of their princes; yet those princes being ambitious of divine honour, give sufficient testimony, that they believed, nothing ought to be sworn by, but the Deity.
16. And seeing men cannot be afraid of the power they believe not, and an oath is to no purpose, without fear of him they swear by; it is necessary that he that sweareth, do it in that form which himself admitteth in his own religion, and not in that form which he useth, that putteth him to the oath. For though all men may know by nature, that there is an Almighty power, nevertheless they believe not, that they swear by him, in any other form or name, than what their own (which they think the true) religion teacheth them.
17. And by the definition of an oath, it appeareth that it addeth not a greater obligation to perform the covenant sworn, than the covenant carrieth in itself, but it putteth a man into a greater danger, and of greater punishment.
18. Covenants and oaths are de voluntariis, that is, de possibilibus. Nor can the covenantee understand the covenanter to promise impossibles; for they fall not under deliberation: and consequently (by chap. XIII, sect. 10, which maketh the covenantee interpreter), no covenant is understood to bind further, than to our best endeavour, either in performance of the thing promised, or in something equivalent.
