27. For I know thy rebellion. The reason is given why he passed over the utility of his doctrine, and only cited it as a witness against the Israelites in terms of severity and reproach, viz., because he had found them by experience to be of a “stiff neck,” (of which expression I have spoken elsewhere,) and has no confidence that they will be more tractable hereafter. He argues from the less to the greater; for, if, while such a leader as theirs was alive, they were rebellious, they were likely to assume greater audacity when he was dead. For we know of what avail is the authority of a great and excellent person to restrain the licentiousness of a people. At the same time, Moses does not arrogate so much to himself as to say that the good condition of the people depended upon his presence, but, pointing out their danger, he seeks to render them more obedient after his death.