Of the different types of Islamic knowledge, which knowledge has the highest merit? What is the merit of the knowledge of Tawhid over other types of knowledge?
The knowledge of Tawhid has an honored merit over other types of knowledge because it relates to the most honored information. The high honor of the knowledge is derived from the status of what one is learning about. Since the knowledge of Tawhid conveys the knowledge about Allah, clears Allah of what is not befitting to Him, and clears the Prophets of what is not befitting to them, it is better than the knowledge of the Rulings. Allah said in Surat Muhammad verse #19
﴿ فاعلم أنه لا إله إلاّ الله واستغفر لذنبك ﴾ سورة محمد
The verse means: [know (be steadfast), O’ Muhammad, that no one is God except Allah and ask Allah for forgiveness].
Imam Abu Hanifah said in his book Al-Fiqh al-’Absat: “Know that the knowledge of the essentials of the Religion is better than the knowledge of Rulings.”