Genesi 50:6

And Pharaoh said, Go up, and bury thy father, according as he made thee swear.

Ver. 6. As he made thee swear.] Oaths must be religiously kept, even those that are private, betwixt friend and friend. For, although whatsoever is more than yea and nay, in our ordinary communication, is evil, Mat 5:37 yet a private oath, as betwixt Boaz and Ruth, so it be sparingly and warily used, is not unlawful. For in serious and weighty affairs, if it be lawful in private to admit God as a judge, why may he not as well be called to witness and to avenge? But this only in case of necessity, when yea and nay will not be taken.