Translation of the verse 19 from Surah Ad-Dukhan : Number of verses 59 - - page 497 - Part 25.
"And exalt not (yourselves) against Allah. Truly, I have come to you with a manifest authority.
And [saying], "Be not haughty with Allah. Indeed, I have come to you with clear authority.
(44:19) and do not exalt yourselves in defiance of Allah. I have come to you with a clear authority *18 (as a Messenger).
*18) In other words, it means: "Your rebellion against me is in fact rebellion against Allah, for what annoys you is not what I say but what Allah says, and I only present those things as His Messenger. If you doubt whether I have really ban sent by Hun or not, I present before you a clear authority of my appointment from Allah. " This authority does not imply any one miracle but a long series of the miracles which the Prophet Moses continued to show to Pharaoh and his people for years since the time he $roved in the court of Pharaoh till his last days in Egypt. Whatever Sign they denied, was followed up by a greater Sign of authority by him. (For explanation, see E.N.'s 42, 43 of Az-Zukhruf).