It is very human (with all the ‘I can decide to give meaning to things’ ego-centrism included) to say that a ‘messenger of God’ was someone of great moral character. It is the urge people have to extol, morally, their favorite person. It’s what one would like to do, for instance, for one’s father or elder – one would like to (even if one can’t because of not having a father or elder of moral boast). It is to feel one is on the right path MORALLY! that one is GOOD and one belongs to people who are good and whose leader/father is good. This claim about the goodness of the person KILLS that person as a messenger of God!
That humans would do this – and they do this – is known to the maker. Hence the importance of the verse (and its strangeness for those who just look at it and say ‘but who says he is our father?!’ I never say that!).
33:40
“Muḥammad is not the father of anyone of your men, but rather he is the Messenger of God and last/seal the of the callers. And ever is Allah, of all things, Knowing.”
Messenger, caller unto God, the bearer of a message ABOUT God, NOT about HIMSELF! A messenger is truly denied messengership not when he is called a man of mediocre character. He is denied messengership when one says that YOU are such a MORAL man and that the perfections you bear are NOT messages about WHO your Lord and My Lord is!
Muhammad’s message made EVERYTHING a caller unto God (by saying la-ilaha to ALL, without exception, of course including himself). Insofar as nothing can be added to the list of things in reality (inside humans and out in the world and in all the relations that display any good quality) that tell us about NOT themselves but about GOD, no more “message-bearing” is possible. (but of course only if one understands Muhammad turning all of creation into glorifiers of the Maker WITHOUT any share for anyone else).
it is truly a tragedy that people would rather repeat the words of revelation and whatever they hear from others without ever thinking about the meaning of what they say. The “best attributes” of callers to God are the attributes made Divine (they tell us about God) and not about humans who bear them IN HIS NAME.
There is nothing that kills a messenger more than denying that all things carry messages about their source, God. Nothing denies this more than making ignorant claims about how great and moral a character the Prophet possessed.
The natural religious piety of man, and his creation of moral exemplars, will always be the last fort of resistance against revelation’s negation of all deity except the One owner of all that is good. Messengers take us to God. Morality takes us to the human character. God help me and help you and help everyone! Muhammad for most people is the father of us and not a messenger of God. and most are willing to kill for their idol than to heed the truth of revelation.
The Quran as Revelation 