Who are al-Bukhari's most important teachers?

Imam Al-Bukhari, Muhammad ibn Ismail ibn Ibrahim, was born in Shawwal in the year 194 AH and passed away in the year 256 AH. He memorized the compilations of Ibn Al-Mubarak when he was young, and at the age of eighteen, he compiled the issues of the Companions and the Tabi'in. Then, he compiled Al-Tarikh (History) at the Prophet's grave during moonlit nights. He memorized one hundred thousand sound hadiths and two hundred thousand unsound hadiths.

Al-Bukhari narrated from one thousand and eighty shaykhs. The importance of these shaykhs varied according to their scholarly standing, the frequency of Al-Bukhari's narrations from them, and the elevated chains of narration they possessed.

Among his shaykhs from whom he narrated extensively are: Abdullah ibn Yusuf Al-Tinnisi, Ali ibn Abdullah Al-Madini (about whom Al-Bukhari said: "I never felt humbled before anyone except Ali ibn Al-Madini"), Abu Al-Yaman Al-Hakam ibn Nafi', and others.

Among those of moderate narration are: Abdul Aziz ibn Abdullah Al-Owaysi, Abdullah ibn Al-Zubayr Al-Humaydi, and others.

Among his shaykhs who were also imams are: Imam Ahmad ibn Hanbal, Ishaq ibn Rahawayh, and Ahmad ibn Salih Al-Misri.

Ibn Hajar categorized Al-Bukhari's shaykhs into five classes: 1. The first class: Those who narrated to him from the Tabi'in. 2. The second class: Those who lived in the same era as the first class but did not hear from trustworthy Tabi'in. 3. The third class: The middle class, who did not meet the Tabi'in but took knowledge from the prominent followers of the Tabi'in (kibar tab' al-atba'). 4. The fourth class: His companions in seeking knowledge, and those who heard a little before him. 5. The fifth class: People who were considered his students in age and isnad (definition), from whom he heard for benefit.

Al-Bukhari said: "A Muhaddith (hadith (definition) scholar) is not complete until he writes from those who are above him, those who are like him, and those who are below him."