This term relates to ‘Qufl’, i.e. work related to locks. The personality famous in this relation is a Shafi’i Shaykh, Imam Abu Bakr Abdullah Bin Ahmad Marwazi رَحْمَةُ اللّٰهِ عَلَيْه. He is called Al-Qaffaal-ul-Sagheer [اَلْقَفَّالُ الصَّغِیْر]. He was born in 327 AH, and he passed away in 417 AH. He was a locksmith with such great expertise that with the help of his tools and key, he once manufactured a lock that merely weighed 4 habbah (i.e. a very light lock whose weight was equivalent to the weight of only 8 grains of barley). When he reached the age of 30, he left this profession and paid attention to ‘gaining Islamic knowledge’. Afterwards, he attained such a prominent position in Fiqh [Islamic Jurisprudence] that Faqeeh Nasir-ul-‘Umari رَحْمَةُ اللّٰهِ عَلَيْه has stated: ‘Imam Abu Bakr Qaffaal رَحْمَةُ اللّٰهِ عَلَيْه was second to none in Fiqh in his era and afterwards as well.’ His student, Qazi Husain رَحْمَةُ اللّٰهِ عَلَيْه has stated: While teaching, the honourable teacher would weep (keeping his head lowered) most of the time; he would then lift his head and say, ‘we are so heedless of our aim’.
Note: One more pious predecessor was also famous as Qaffaal [قَفَّال] in the past. His name is Sayyiduna Abu Bakr Muhammad Bin Ali Ash-Shashi رَحْمَةُ اللّٰهِ عَلَيْه. He is known as Al-Qaffaal-ul-Kabeer [اَلْقَفَّالُ الْکَبِیْر]. (Al-Ansaab lil-Sam’aani, vol. 10, pp. 211, Sayar-e-A’lam-un-Nubala vol. 13, pp. 60)
This term relates to ‘Al-Qutn’, i.e. selling cotton. The personality famous in this relation is the great Imam, Ameer-ul-Mu’mineen in the field of Hadees, Sayyiduna Yahya Bin Sa’eed رَحْمَةُ اللّٰهِ عَلَيْه. He was born in the beginning of 120 AH, and he passed away in Safar, 198 AH. Hafiz-ul-Hadees, Ibn-e-‘Ammar رَحْمَةُ اللّٰهِ عَلَيْه has stated: ‘If you see Sayyiduna Yahya Bin Sa’eed رَحْمَةُ اللّٰهِ عَلَيْه, due to his apparent appearance as a trader, you will presume that he will not be having profound knowledge. However, when he would speak, Islamic jurists would become quiet to listen to him [attentively].’ Abdur Rahman Bin Mahdi رَحْمَةُ اللّٰهِ عَلَيْه has stated: When Sayyiduna Sufyan Sawri رَحْمَةُ اللّٰهِ عَلَيْه came to Basra, he said to me, ‘bring a [scholarly] human to me so that I may have a scholarly discussion with him.’ So, I brought Sayyiduna Yahya Bin Sa’eed رَحْمَةُ اللّٰهِ عَلَيْه, and they both engaged in a scholarly discussion. When Sayyiduna Yahya Bin Sa’eed رَحْمَةُ اللّٰهِ عَلَيْه left, Sayyiduna Sufyan Sawri رَحْمَةُ اللّٰهِ عَلَيْه said to me, ‘I had asked you to bring a human being but you brought a Jinn’ (i.e. he was surprised by the excellent memory of Sayyiduna Yahya Bin Sa’eed رَحْمَةُ اللّٰهِ عَلَيْه). (Sayar-e-A’lam-un-Nubala, vol. 8, pp. 110-117)
This term relates to ‘Aajurr [آجُرّ]’, i.e. the work related to bricks, and selling bricks. Moreover, it also refers to Darb-ul-Aajurr [دَرْبُ الْآجُرّ] (an area in Baghdad). Some pious predecessors are known with this relation due to being engaged in brick making, and some due to living in the aforementioned area of Baghdad. The pious predecessor, Sayyiduna Muhammad Bin Khalid Aajurri رَحْمَةُ اللّٰهِ عَلَيْه is also amongst the personalities who are famous as Aajurri. He departed this life in 303 AH.
He رَحْمَةُ اللّٰهِ عَلَيْه has stated: I was engaged in brick-related profession; I was once passing between the layers of bricks when I heard that one layer of bricks said Salam to the other, and it [further] said, ‘I will be thrown in fire tonight’. He has further stated: ‘I instructed labour not to put that layer in fire, and the bricks remained in the same state at their place. After that event, I never engaged in baking bricks in fire’. (Al-Ansaab lil-Sam’aani, vol. 1, pp. 94, 95; Al-Muntazim Li-Ibn-il-Jauzi, vol. 13, pp. 164)
 One Habbah is equivalent to the weight of two grains of barley