Abdallah b. Mas'ud said, “I know the comparable <i>suras</i> which the Prophet (ﷺ) used to join together; ” and he mentioned twenty <i>suras</i> at the beginning of <i>al-Mufassal</i>,1 according to Ibn Mas'ud’s arrangement, two in a <i>rak'a</i>, the last of them being <i>H. M. ad-Dukhan</i>,2 and “About what do they ask one another?”3 1. A title given to the <i>suras</i> from 49 to the end, but several other <i>suras</i> are also mentioned:

37, 45, 47, 48, 50, 61, 67, 87, and 93. The name is most appropriately explained ay meaning that this is the section of the Qur’an which contains many shorter suras. 2. Al-Qur’an; 94. As this is included as one of the <i>suras</i> in <i>al Mufassal</i>, it suggests that this section begins earlier than the first number mentioned in the note referred to above. 3. Al-Qur'an; 78. (Bukhari and Muslim.)

وَعَنْ عَبْدِ اللَّهِ بْنِ مَسْعُودٍ قَالَ: لَقَدْ عَرَفْتُ النَّظَائِرَ الَّتِي كَانَ النَّبِيُّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ يَقْرِنُ بَيْنَهُنَّ فَذَكَرَ عِشْرِينَ سُورَةً مِنْ أَوَّلِ الْمُفَصَّلِ عَلَى تَأْلِيفِ ابْنِ مَسْعُودٍ سُورَتَيْنِ فِي رَكْعَةٍ آخِرُهُنَّ (حم الدُّخان) و (عَم يتساءلون)