Anas reported the Prophet as saying, "The most compassionate member of my people towards my people is Aba Bakr, the most rigorous regarding God's affair is `Umar, the most genuinely modest is `Uthman, the one who knows most about obligatory duties is Zaid b. Thabit, the one who knows best how to recite the Qur'an is Ubayy b. Ka b, and the one who has most knowledge about what is lawful and what is prohibited is Mu`adh b. Jabal. Every people has a trustworthy guardian, and the trustworthy guardian of this people is Abu `Ubaida b. al Jarrah. Ahmad and Tirmidhi transmitted it, Tirmidhi saying this is a hasan sahih tradition. It is also transmitted in mursal form, on the authority of Ma'mar who cited Qatada as his authority, and it contains the phrase "The most learned in legal matters is `Ali."