SHAFAQNA – Ibrahim ibn Abbas narrated: In all the times that I was with Imam Ridha/Reza (AS), I took part in various gatherings, and I never saw any one to answer questions better and more eloquently than Imam (AS) on any issue including religious matters and others. Imam (AS) was fully knowledgeable about various sciences and technologies, and the answers he used to give were very convincing at excellent level. Ma’mun (the Caliph of the time) always tried to test Imam Ridha (AS) in many occasions but failed to gain the upper hand in any subject or issue.
All the answers given by Imam (AS) were according to the noble verses of the holy Quran. Imam Ridha (AS) used to recite the Quran completely every three days and used to say: If I wanted I can recite the Quran in a shorter time, but I contemplate on every single Ayah that I recite, and think about the connection of the Ayah with the relevant event or issue, and when that particular Ayah has been descended, and I never pass quickly a subject in any Ayah; and that is why it takes me three days to recite the holy Quran completely .
 Beharul Anwaar, Vol. 49, Page 90.