Hadith Collection And Compilation
There was no work initiated to compile or collect hadith during the time of Caliphs. The khulafa were busy in spreading Quran in the ummat during their time. The Khulafa including Ali bin Abi Talib Discouraged reporting the hadith. This was done intentionally so that Quran would get highlighted in Muslim Ummah instead of Hadith. They feared that Quran would be sidelined hence they reported as few hadith as possible. Also they feared for errors in reporting.
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