He is Abu Muhammad Abdullah bin Sa'eed bin Muhammad bin Kullaab al-Qattan al-Basri. He was one of the Mutakallimoon (speculative theologians) during the time of al-Ma'moon, and he had debates and works against the Mu'tazilah, and the "Kullaabiyyah" are ascribed to him. He has a number of works that are documented such as "Kitaab as-Sifaat", "Khalq Af'aal" and "ar-Radd 'ala al-Mu'tazilah". These books are lost, however remnants of them can be found in other works such as al-Maqaalaat of Abu al-Hasan al-Ash'ari, and also in the works of Ibn Taymiyyah and Ibn al-Qayyim, and he is also quoted by the early Ash'ari Scholars such as Ibn Fawrak (d. 406H), and some of them, such as "Kitaab us-Sifaat" are mentioned by Ibn an-Nadim (d. 385H) in his "Fihrist" (Catalogue), who referred to him as a "From amongst the Hashawiyyah", and Ibn Hajr al-Asqalani explained this statement in "Lisaan ul-Meezaan" to mean that he (Ibn Kullaab) was upon the way of the Salaf in leaving the ta'weelaat (figurative explanations) of the verses and hadeeths related to the Attributes. Ibn Kullaab died around or after 240H.

Ibn Kullaab and the Ash'ariyyah

Ibn Kullab is the true and real author of what became known as the creed of the earlier Ash'aris, and Abu al-Hasan al-Ash'ari adopted the creed of Ibn Kullab as Ibn Kullaab had much in the way of refutation of the Mu'tazilah - whom al-Ash'ari had abandoned. Ibn Kullaab tended towards the Hadeeth and the Sunnah and had good positions, however he tried to tread a middle ground between the Mu'tazilah and the people of the Sunnah and this explains elements of his creed such as adopting the sifaat dhaatiyyah (attributes of the essence) for Allaah but negating the Sifaat Fi'liyyah (attributes of action), and inventing the idea of "Kalaam Nafsee" (the eternal speech in the self of Allaah) in order to flee from the saying that the speech of Allaah is created - amongst many other views, and this is a subject on its own so it can be left for another article inshaa'Allaah.

Abu Mansur Abdul-Qahir al-Bagdhadi on Ibn Kullaab on the Issue of al-istiwaa

And Abu Mansur Abdul-Qahir al-Bagdhadi (d. 429H) who is a prominent Imaam of the Ash'aris and whose works constitute foundational texts (especially "Usool ud-Deen"), makes mention of Abdullaah bin Sa'eed bin Kullaab alongside Abu al-Abbas al-Qalanisi who he refers to as an "Imaam of Ahl us-Sunnah". Abu al-Abbaas al-Qalanisi was a contemporary of Abu al-Hasan al-Ash'ari.

Here is the front cover to his book, "Usool ud-Deen" (Istanbul, 1928):

Ibn Kullaab's and Al-Qalanisi's position is quoted by Abdul-Qahir al-Baghdadi in the same book, "Usool ud-Deen". Here are pages 112-113:

In these pages al-Baghdadi brings the heading, "The Fifteenth Issue Regarding This Foundation: On the Meaning al-istiwaa Annexed to Him [Allaah]". Then he mentions the various differences on the issue and he describes the opinions of the factions:

• Those who make ta'weel of al-istiwaa (ascendig) to al-Isteelaa (conquering), and about which he says, "This ta'weel is baatil (futile)..." - and it is amazing that from the contemporary Jahmite Ash'aris are those who still use this ta'weel.

• The Mushabbihah, such as the Karraamiyyah, who claim that Allaah's istiwaa upon the Throne is with Him being in contact with the Throne. Then amongst this faction are those who dispute as to whether He is equal to or greater than the Throne in extent.

Then he mentions about the differences on the issue amongst themselves (i.e. referring to himself and the Ash'arite theologians):

• Amongst them are those who say the verse of al-istiwaa is amongst the ambiguous texts (mutashaabihaat) whose interpretation is only known by Allaah. And al-Baghdadi claims that this is the view of Imaam Malik and the jurists of Madinah - and this is an erroneous claim regarding Imaam Malik, for Malik affirmed that "al-Istiwaa ma'qool (Istiwaa is understood)" and in other narrations, "al-Istiwaa ghayr majhool (Istiwaa is not unknown)" and he denied the kaifiyyah by saying "wal kayf majhool (and how is unknown)". And the kaifiyyah of something can only be negated if its meaning is known - as for when something does not have any meaning to begin with, then there is no purpose in negating a kaifiyyah for it. So this is an error in ascribing this to Imaam Maalik.

• Then al-Baghdadi continues and mentions the view of those that al-istiwaa is an act that Allaah creates within the Throne itself which is referred to as al-istiwaa and it is not actually an action of Allaah - and says that this is the view of Abul-Hasan al-Ash'ari - and this was the earlier view of al-Ash'ari before he adopted the saying of the People of the Sunnah which is affirmation of al-istiwaa for Allaah.

Then he mentions the last view, saying:

And amongst them are those who say that His istiwaa (ascending) over the Throne is His being above the Throne without contact (mumaassah), and this is the saying of al-Qalanisi, and Abdullah bin Sa'eed [Ibn Kullaab], he mentioned it in "Kitaab us-Sifaat".

Then after this al-Bagdhadi details what he believes to be the correct view which is that the Throne (al-Arsh) is a metaphor for Allaah's dominion (mulk) and this is a false and baseless ta'weel in light of the Book and the Sunnah and it is rejected by the likes of al-Bayhaqi - who is considered an Ash'ari - (see here) and it opposes what is held by Ahl us-Sunnah unanimously that the Throne is a true and real created entity.