If someone were to recite some verses of the Mighty Qur’an in one of his classes, he would proceed to explain them, and his class would end with this. His class would last for a good portion of the day, and he did not have a designated person to recite for him predetermined
verses that he would prepare for. Rather, any random person who was attending his class would recite what was easy for him, and Ibn Taymiyyah would then explain whatever was recited. He would usually not stop except that those in attendance would know that were it
not for the lack of time, he would have delved into what he was explaining from many, many more angles. However, he would stop in order to allow his listeners to rest.
For example, he delivered a tafsir of “Say, He is Allah, One.’”  that took up an entire huge volume. Also, his tafsir of “The Beneficent ascended the Throne.”  filled around 35 volumes, and I have been told that he began compiling a tafsir that would have taken up fifty volumes had he completed it.
1. surah al-Ikhlas 1 [112:1]
2. surah Ta Ha verse 5 [20:5]
Taken from ‘The lofty virtues of Ibn Taymiyyah’
By The Imam, the Hafidh Abu Hafs ‘Umar bin ‘Ali al-Bazzar
Translated By Abu Sabaayaa