Salaam alaikum , Thanks Joseph islam and optimist for giving your time to reply on my post.
I understood it sir. 16:63 is words of angel , the angel says 'By Allah' , we (angels and god , on the command of god alone) sent to the nations before you .
Sahih international uses the word messenger in brackets to explain it , but now after viewing your explanation i think 'warning or good news' makes more sense here.knowing arabic grammer , what are your views on it sir .
Thank you.