Leviticus 5:3-4

VIN(i) 3 Or if he touch the uncleanness of man, whatever his uncleanness be with which he is unclean and it is hid from him, when he knows of it, then he will be guilty. 4 »When you pledge a vow in haste about what you will or will not do, as some people do, and then ignore it; although you know what you said, you will be guilty.