Reference: Badāi’ al-Fawāid Vol. 3 Page 175.
Ibn Aqīl said,
“Abu Isḥāq al-Fayrūzabādi  would never give charity to a poor person before renewing his intention.
He would never speak about a knowledge-based issue except preceding it by seeking the help of Allāh and ensuring his intention was sincere in making the truth prominent, without making it appear good and beautiful to people.
He never authored a book until he first prayed 2 Raka’ah.
It is no wonder, therefore, that his name became well-known, and his works became widespread in the east and west. And this is the blessed effect of sincerity.”
 He is Abu Isḥāq Ibrāhīm Ibn ‘Ali Ibn Yūsuf al-Firūzabādi ash-Shairazi [died: 476h].
“Al-Fayrūzabādi” refers to his place of birth, Firuzabad in modern-day Iran.
“Ash-Shairazi” refers to the city of Shiraz, in the Fars province, Iran. He moved there from Firuzabad in order to seek knowledge from the scholars there.
He was an Imām, Faqīh, Usūli, from the well-known Shāfi’ī scholars, in fact, he is often given the honorific title of: “Shaykh ash-Shāfi’iyyah”.
His authored works include:
- At-Tabṣira fī usūl al-Fiqh [537 pages]
- At-Tanbīh fil Fiqh ash-Shāfi’ī [678 pages]
- Al-Lama’ fī usūl al-Fiqh [134 pages]
- Al-Ma’ūnah fi al-Jadal [127 pages]
- Al-Muhadhab fī fiqh al-Imām ash-Shāfi’ī [3 volumes]
- Tabaqāt al-Fuqahā [191 pages]
المرجع: فبدائع الفوائد
قال ابن عقيل: “كان أبو إسحاق الفيروزأبادي لا يُخرج شيئاً إلى فقير إلا أحضر النية، ولا يتكلم في مسألة إلا قدم الاستعانة بالله وإخلاص القصد في نصرة الحق دون التزيين والتحسين للخلق. ولا صنف مسألة إلا بعد أن صلى ركعتين فلا حرج أن شاع اسمه واشتهرت تصانيفه شرقاً وغرباً، وهذه بركات الإخلاص.”