Hence you may see what to think of the common determination of casuists concerning vows materially sinful, when they say, a man is not obliged to keep them. It is only thus far true, that God obligeth him not to do that particular thing which he voweth, for God had before forbidden it, and he changeth not his laws upon man's rash vowings; but yet there is a self-obligation which he laid upon himself to do it: and this self-obligation to a sinful act, was itself a sin, and to be repented of, and not performed; but it bringeth the person under a double obligation to penalty, as a perjured person, even God's obligation who bindeth the perjured to penalty, and the obligation of his own consent to the punishment, if there was any oath or imprecation in the vow. If it were true that such a person had brought himself under no obligation at all, then he could not be properly called perjured, nor punished as perjured; but he that sweareth and voweth to do evil, (as the Jews to kill Paul,) though he ought not to do the thing, (because God forbiddeth it,) yet he is a perjured person for breaking his vow, and deserveth the penalty, not only of a rash vower, but of one perjured. Thus error may make a man sinful and miserable, though it cannot warrant him to sin. _Direct._ II. Try well the matter of your vows, and venture not on them till you are sure that they are not things forbidden: things sinful or doubtful are not fit matter for a vow: in asserting, subscribing, and witnessing, you should take care, that you know assuredly that the matter be true, and venture not upon that which may prove false; much more should you take care that you venture not doubtingly in vows and oaths. They are matters to be handled with dread and tenderness, and not to be played with, and rashly ventured on, as if it were but the speaking of a common word: "Be not rash with thy mouth, and let not thy heart be hasty to utter any thing before God," Eccles. v. 2. It is a grievous snare that men are oft brought into by ignorant and rash vows;[48] as the case of Jephthah, and Herod, and many another tell us for our warning: an error in such cases is much more safely and cheaply discerned before, than afterwards. To have a rash vow or perjury to repent of, is to set a bone in joint, or pull a thorn out of your very eye; and who would choose such pain and smart? "Suffer not thy mouth to cause thy flesh to sin; neither say thou before the angel that it was an error: wherefore should God be angry at thy voice, and destroy the work of thy hands," Eccles. v. 6. "It is a snare to the man who devoureth that which is holy, and after vows to make inquiry," Prov. xx. 25. Be careful and deliberate to prevent such snares.