And it is the way of Allah from ever that makes the prophets...
And it is the way of Allah from ever that makes the prophets to convey the message of Allah without any hesitation, without taking anything else into their consideration. After that comes this verse; and it cuts at the roots of all such objections of the enemies of the Holy Prophet (S). Their first objection was that the Holy Prophet had married his daughter-in-law, which is forbidden in Islam. Replying to that, Allah said: "Muhammad was not father of anyone from among your men folk".
It reminds the unbelievers that Zaid bin Haritha (whose divorcee Zainab was), was not the son of the Holy Prophet, and as such Zainab was not the daughter-in-law of the Holy Prophet. Marrying the divorcee of Zaid therefore cannot be said to be forbidden by any logic. Even his enemies knew that Muhammad was not the father of Zaid. Second objection: Agreed that Zaid was not the son of the Holy Prophet by birth; but was he not his son by adoption?
Agreed that it was not illegal for Muhammad to marry the divorced wife of Zaid. But was that marriage necessary? Agreed that that marriage was legal and lawful. But what was the need of entering into such a marriage which could make Muhammad Al-Mustafa (S) the target of ridicule? Replying to that, Allah said: "But Muhammad is the messenger of' Allah".
The significance of this answer is that, being a Messenger of Allah, it was essential for him to remove all superstitions and prejudices and all baseless taboos which were choking the life out from the society. It was essential for him to act in such a way that nobody could remain in any doubt about the legality of such marriages and about the fact that an adopted son was not a son at all. Then comes the phrase: "'The Last of The Prophets".
The significance of this phrase is that, after the Holy Prophet of Islam not even a prophet is to come (let alone a Rasul whose job is to bring a new Shari'ah). No prophet was to come after him, so that if any deficiency were left unreformed in the legal or social system of the society or religion, the later prophet would remove that defect. Muhammad Al-Mustafa (S) was the last Messenger; he was the Last Prophet.
And therefore it was essential for him to effect reforms to all the bad practices of the society, to refute all superstitions during his lifetime, because there was no Nabi to come after him, let alone a Rasul. Then comes the sentence:" And Allah has the full knowledge of everything". Why this assertion?