Years of studying Islam brought Montgomery Watt, an Orientalist scholar, to this conclusion:
“The other main allegations of moral defect in Muhammad (Peace and Blessing of Allah Be Upon him) are that he was treacherous and lustful . . . Sufficient has been said above about the interpretation of these events to show that the case against Muhammad (Peace and Blessing of Allah Be Upon him) is much weaker than is sometimes thought.The discussions of these allegations, however, raises a fundamental question. How are we to judge Muhammad (Peace and Blessing of Allah Be Upon him) ? By the standards of his own time and country ? Or by those of the ‘most enlightened’ opinion in the West today?
When the sources are closely scrutinized, it is clear that those of Muhammad’s (Peace and Blessing of Allah Be Upon him) actions which are disapproved by the modern West were not the object of the moral criticism of his contemporaries. They criticized some of his acts, but their motives were superstitious prejudice or fear of the consequences.
If they criticized the events at Nakhlah, it was because they feared some punishment from the offended pagan gods or the worldly vengeance of the Meccans. If they were amazed at the mass execution of the Jews of the clan of Qurayzah, it was at the number and danger of the blood-feuds incurred.
The marriage with Zaynab seemed incestuous, but this conception of incest was bound up with old practices belonging to a lower, communalistic level of familial institutions where a child’s paternity was not definitely known; and this lower level was in process being eliminated by Islam . . .
From the standpoint of Muhammad’s (Peace and Blessing of Allah Be Upon him) time, then, the allegations of treachery and sensuality cannot be maintained. His contemporaries did not find him morally defective in any way.
On the contrary, some of the acts criticized by the modern Westerner show that Muhammad’s (Peace and Blessing of Allah Be Upon him) standards were higher than those of his time. In his day and generation he was a social reformer, even a reformer in the sphere of morals.He created a new system of social security and a new family structure, both of which were a vast improvement on what went before.
By taking what was best in the morality of the nomad and adapting it for settled communities, he established a religious and social framework for the life of many races of men. That is not the work of a traitor or ‘an old lecher’.”
Barak Allah ‘Alaykum