When shia are asked: Where is concept of 12 masoomeen in Quran? they reply: Where are details of Salah in the Quran?
This is classic #Whataboutism or Comparing apples and oranges (Comparing 2 things that can NOT be compared)
Imamate = #Article of shia faith.
#Salah is NOT article of #Sunni faith.
Shia consider Imamah to be Usool-e-Deen (fundamental of religion) whereas Salat (prayer) is Furoo-e-Deen (subsidiary and secondary part of religion). Hence, the comparison between the two is unfair, because Salat is considered an Islamic ritual (a Fiqh matter) whereas Imamah is considered essential to the core belief of Islam, on the same level as Tawheed, Prophethood, and the Day of Judgment.
Imamah is important enough to convince the Shia to separate themselves from the mainstream Islam. If the only difference between the Shia and mainstream Muslims was the way they perform prayer, then they would never have become a sect outside of orthodox Islam.
Having said that, the reality is that Salat has been referred to explicitly and strongly more than 700 times in the Quran. In each of these verses, one of the aspects of prayer is covered. Many of the verses talk about the details of prayer, such as how to come prepared for prayer (ablution), prayer in travel, and other such matters. So we wonder why the Shia would compare Salat with Imamah. Salat is mentioned over 700 times, whereas Imamah is never mentioned.
Certainly, with such a vast and strong reference to Salat from Quran, Muslims will refer to the Prophet (صلّى الله عليه وآله وسلّم) to know the details. Nobody is saying that the Quran should contain the nitty-gritty of where our hands should be placed while praying and other such minor Fiqh issues. But the concept of Salat is very much stressed in the Quran; again and again, Allah (عز و جل) says that the believers are those who establish Salat. There is not a single reference to Imamah; had Imamah been simply outlined in the Quran, then the Muslims could refer to the Prophet (صلّى الله عليه وآله وسلّم) for the nitty-gritty details such as how much Khums to pay to the Imam and other such minor Fiqh issues. And yet, Imamah is never mentioned even fleetingly.
The truth is that Imamah is an imaginary concept concocted by the Shia scholars and it does not exist. If it existed, it would be in the Quran; its absence from the Quran is evidence of its imaginary nature. Salat is mentioned 700 times, and yet we find zero verses in the Quran about “Infallible Imams;” even the name of Ali (رضّى الله عنه), the leader of these Imams, is not mentioned.
We wonder why Salat is mentioned so many times in the Quran, but there is absolutely no mention of the 12 Imams, the Infallible Imamah, or even the divine Imamah of Ali (رضّى الله عنه)? The Shia believe that Imamah is Usool-e-Deen (i.e. primary) whereas Salat is Furoo-e-Deen (i.e. secondary). So why would a minor point be mentioned so many times and not the major one?
In Islam, it is Haram to enter someone else’s house without first knocking on the door and getting permission. This is mentioned in the Quran.
How come something so miniscule as this could be mentioned in the Quran and yet we find nothing on the “all-important” concept of Imamah, which is supposedly the main pillar of belief? And consider this with Allah’s (عز و جل) declaration: “We have left nothing out in the Book.” (Quran, 6:38)