It is Western historians who blame the whole episode on the Prophet. Forgetting the fact that Qurayza, by breaking their word, had become outlaw, and by doing it in war, they were punished in the extreme way we still punish traitors. Treason has always been met with capital punishment, in both East and West. And for the Jewish tribe to betray their allies in the most critical juncture of the war, was even worse. The point here is, the Prophet did not pass judgement for the Qurayza to be executed, and even if he did, military and political convention gives him the justification to do so for what the Jewish tribe did. The women and children of the Qurayza were sold into slavery, but interestingly, guess who mass participated in this commercial endeavour?. The Jews of Madinah.
Betty Kalen in her book “Muhammad the Messenger of God” says in a conlcuding note on this episode
“It is really quite fruitless to fix blame on a desert chieftan for behaving according to the customs of his kind or to wonder why God should speak to us through such a man. It is better to look at the deeds of man at large and wonder that God should choose to speak to us at all.”
Honestly, what is wrong with your basic history of Islam?. Madina (or Medina) was never brutally overtaken, the Prophet was welcomed to the city in 622CE (not 632CE, the year the Prophet died). And Makkah (or Mecca) peacefully surrendered in 630CE. And the Prophet gave clemency to all those who used to persecute him.
The Prophet never attacked caravans (unless in a state of warfare of the opposing army). It was the succeeding centuries in which bands of nomadic Arabs did so. This is no fault of the Prophet. We don’t accuse Jesus for the Crusades, inquisitions and colonial exploitation that were done by Christians, in his name also.
Islam was never spread by the sword, if that was so their would not be a single Arab Christian walking the Earth today. It was the truth of Islam that brought my forefathers into its fold, and brings many adherents everyday. The Quran makes no mention of sword, and Western historians today acknowledge that Islam was never spread by force. Unlike Jesus (pbuh), the slaughtered Lamb, who said:
“Think not that I am come to send peace on earth: I came not to send peace, but a sword.” --Matt 10:34
Suppose ye that I am come to give peace on earth? I tell you, Nay; but rather division: —LUKE 12:51
But those mine enemies, which would not that I should reign over them, bring hither, and slay them before me. --LUKE 19:27
I’m sure the Prince of Peace if given a bit more time, his words would have translated into action. The intention says more the action in many cases. --Regards Malik Ali