Most religions came into being thousands of years ago. Everything that was relevant then is not relevant now. Some of them have evolved with changing times and some still need to...
He knows that in my opnion otherwise why ther would have been need for 100+ thousand prophets in total as per Islam.
There could be only two reasons for it
(1) Text gets lost or corrupted but that could have been easily fixed by god by giving a book not through word of mouth but through a actual hard-copy that way therw woudl have been no room for unmindful corruption.. Mindful cprruption still could have cropped in and that cud crop in any text
(2)With changing times new set of rules are needed hence new prophet.. For instance in early days incest must have been allowed because there was no other way of perpetuation of human race from one couple of adma and eve.> later oninbreeding was to be hazardous so needed to be banned
My point being requirements of mankind seems like evolvign hence religious code too must keep pace.. In that case question arises how do you recocnile with concept of last prophet why there is no need of further revision of code with changing time.
To many questions which has no answers