Exodus 8:9

Glory over me That is, I yield to thee. Thou shalt command me. As I have gloried over thee in laying, first my commands, and then my plagues upon thee; so now lay thy commands upon me for the time of my praying, and if I do not what thou requirest, I am content thou shouldest insult over me. Or he may mean, Glory or boast thyself of or concerning me, as one that by God's power can do that for thee which all thy magicians cannot, of whom thou now seest thou canst not glory nor boast, as thou hast hitherto done. When shall I entreat for thee? Appoint me what time thou pleasest. Thus, he knew the power and glory of God would be most conspicuous in the miracle. And this was not presumption in Moses, who had a large commission, as a god to Pharaoh, and particular direction from God in all he said and did in these matters.