It wasn't really directed to you but more towards a dengerous concept formulating in the minds of some of our dear Brothers and Sisters regarding the Infallibility of our Prophets and Messengers(AS).
The difference between the Creator and the Created are one of category. The Oness of Allah Most High refers to His unique Category and independence from everything which is perfectly understood by Surat Ikhlaas.
If we drag Allah Most High down to our category by trying to compare the uncomparable we will mentally impose limits upon that which is beyond limits and it puts us in the false position of having to belittle the Best of Creation Mohammad(SAW) in order to keep Allah in His place as God. And so another dangerious concept forms in the mind; Prophets and Massengers are flawed, sinners and people who made mistakes which is on par with the belief of Christians and Jews. So if our role models are themselves sinners the gravity of Sin decreases.
However the traditional view of our Pious Predecessors has always been the Prophets and Massengers are protected from even minor Sins:
Qadi `Iyad in al-Shifa' said that the Jumhur of the Jurists from the schools of Malik, al-Shafi`i, and Abu Hanifa, agree that the Prophets are protected from all minor sins because one is required to follow them in the minutest matters. It is even reported from Malik that this is obligatory to believe.
“Allah Most High preserving the Prophets from falling into that which has been prohibited,” as explained by the commentators of the Jawhara. [Tattan/Kaylani, `Awn al-Murid `ala Jawharat al-Tawhid, 2.727; also: Bajuri, Tuhfat al-Murid]
“These are the ones whom Allah has guided, so follow their guidance.” [Qur'an, Surat al-An`am: 90]
The classical definition of amana (trustworthiness), which relates to `isma (being preserved from sin) is:
“Allah Most High preserving the Prophets from falling into that which has been prohibited,” as explained by the commentators of the Jawhara. [Tattan/Kaylani, `Awn al-Murid `ala Jawharat al-Tawhid, 2.727; also: Bajuri, Tuhfat al-Murid]
Another definition of trustworthiness was given by the great 20th Century Hanafi scholar from Hama (Syria), Shaykh Muhammad al-Hamid in his work Rudud `ala Abatil [297, as quoted in the above text],
“It is a trait that Allah creates in His servant through which they are disposed to doing the good and that prevents them from the bad.”
What I am saying is Prophets and Massengers are Perfect in their own right and for their category as role models for us to follow. Only Allah Most High knows the granular differences within them but in our eyes they were perfect which is why they were chosen for those specific roles.
I too am learning so if I err it's your duty to to correct me. Believers are a Mirror for one another.