For this, one has to refer to the reliable books of the school. In the Hanafi school, this would include Imam Sarakhsi’s Mabsut, Imam Kasani’s Bada`i al-Sana`i, Imam Zayla`i’s Tabyin al-Haqa’iq, Imam Marghinani’s Hidaya along with its commentaries, especially the Inaya of Imam Babarti and Fath al-Qadirof Imam Kamal ibn Humam.
Allama Ibn Abidin did a phenomenal job of going through the key works of the school and deciphering the relied-upon position [for most legal issues] in his renowned Hashiya, Radd al-Muhtar. He relies heavily on the above books, as well as the main primary texts (mutun) of the school, including Mukhtasar Quduri,Kanz al-Daqa’iq, the Mukhtar, the Wiqaya, and Multaqa ‘l-Abhur.
The Fatawa Hindiyya is also indispensable.
Then there are also key books for specialized areas, such as:
-For worship: Imam Shurunbulali’s Nur al-Idah and commentaries, Imam Tahtawi’s Hashiya on Maraqi ‘l-Falah, and the Hadiyya ‘l-Ala’iyya.
-For commercial transactions: the Majalla and its commentaries, particularly those by Imams Ali Haydar and Attasi.
-For personal law: Allama Qadri Basha’s Ahkam Shar’iyya fi Ahwal Shakhsiyya, along with Imam Abyani’s commentary.
-For the lawful and prohibited (halal/haram): Imam Nahlawi’s Durar Mubaha fil Hadhr wal-Ibaha.
With respect to modern fatawa, one follows the qualified scholarship of his time and place, as their verdicts are based on the criteria explained above. This knowledge is not taken [only] from the ink of books but rather [primarily] from the hearts of humans.
May Allah give us tawfiq and baraka to learn His religion, for His sake alone. Amin.
Faraz A. Khan
Checked & Approved by Faraz Rabbani