A Few Excerpts from Al-Kafi:
[1] Chapter: The Imams have knowledge of All that was given to the angels and the prophets. (AlKafi vol.1 p.255)
[2] Chapter: The Imams know when they will die, and they only die by their choice. (AlKafi vol.1 p.258)
[3] Chapter: The Imams have knowledge of the past and future; and nothing is hidden from them. (AlKafi vol.1 p.260)
[4] "Obedience to `Ali is true humility and disobedience to him is disbelief in Allah" (Al-Kafi vol.10 p.54)
[5] "Whoever sets up another Imam besides `Ali and delays `Ali's caliphate is a polytheist" (Al-Kafi vol.10 p.55)
Comment (from the author at Ahya): These words declare all Ahl-Sunnah as kufaar (disbelievers) and mushrikeen (polytheists), because we -Ahl-Sunnah- do not believe in the Shia Imamate of `Ali (which is believing that `Ali is Infallible,..etc), also We -Ahl-Sunnah- believe that Abu Bakr (r) is the first caliphate, Omar (r) the second and Othman (r) the third, thus, we delay `Ali's caliphate to be the 4th after Abu Bakr, Omar, and Othman; thus, Shia declare in their most reliable book that Ahl-Sunnah are kufaar and mushrikeen.
[6] The false verse "And We made `Ali your in-law" has been added to Surah Al-InShirah . (Al-Kafi p.289)
[7] Al-Kileeni reported that Jabir asked Abu Ja`far p.b.u.h : "Why `Ali ibn Aby Talib was named Amir-ul-Mumineen?" Abu Ja`far replied: "Allah named him so, and He revealed in His Book" And (remember) when your Lord brought forth from the Children of Adam, from their loins, their seed and made them testify as to themselves (saying): Am I not your Lord, Muhammad is my messenger and `Ali Amir-ul-Mumineen?..." (AlKafi vol.1 p.412)
[8] "Abu Baseer reported that he said to Imam Ja'far, "O' Abu Abdullah(Imam Ja'far as-Sadiq) What is Mus-haf Fatimah?" He replied "It is a Qur'an containing three times what is found in your copy of the Qur'an; yet by Allah, it does not contain even a single letter from your Qur'an. (AlKafi vol.1 p.457)