Why did Imam believe that the gate to divine knowledge would be shut for ever without the Quran?

Seyyed Ahmad Khomeini Admired his Elder Brother

Late Hojjat al-Islam Seyyed Ahmad Khomeini had frequently praised his elder brother martyr Seyyed Mostafa, saying that his sibling was unique in knowledge and has been decorated with divine virtues.

Imam highly trusted Seyyed Ahmad Khomeini

Imam Khomeini had highly trusted his learned son during tough years of struggle against the Shah regime and its backers.

Supplications by Ali ibn Husayn Zain-ul-Abedin contain treasure of mysticism

Imam Khomeini maintained that supplications by Imam, Ali ibn Husayn Zain-ul-Abedin( PBUH), infallible successor of the honorable prophet contain treasure of mysticism and Quranic interpretation.

Imam Hossein (PBUH) saved Islam and justice, Imam Khomeini explained

Imam Khomeini, the late founder of the Islamic Republic once said that matchless sacrifice of the Household of Imam Hossein (PBUH) and his Companions shook the pillars of tyrant rulers of the Umayyads.

Imam Khomeini: The efforts of the prophets of God (‘a) and the purpose behind their appointment ...

Sahifeh-ye-Imam, Vol 14, Page 6

Divine savior will accomplish mission of all divine prophets

Imam Khomeini through his historic speeches described the decisive role of twelfth infallible known as savior in promoting justice in all dimensions among mankind societies.

Imam Khomeini Khomeini defended credibility of Islamic and Shia beliefs

Kashf al-Asrar "Unveiling of Secrets") is a book written in 1943 by Ruhollah Khomeini, the founder of the Islamic Republic of Iran, to respond to the questions and criticisms raised in a 1943 pamphlet titled The Thousand-Year Secrets (Persian: Asrar-i Hazarsala)[1] by Ali Akbar Hakimzadeh. Kashf al-Asrar is the first book that expresses Khomeini's political views.