Shaykh Ibn Uthaymeen (rahimahullaah) said:

Al-Qadariyyah – Their methodology consists of negating Al-Qadar from the actions of the servant and that his desire and ability are independent from the Desire and Ability of Allaah. The first to manifest this view openly was Mu’bad Al-Juhnee, in the last part of the era of the Sahaabah. He learned it from a Majoosee man from Al-Basrah.

They are divided into two groups, one that is extreme and one that is not extreme. The extremist group rejects the attributes of knowledge, desire, ability and creating from Allaah in favor of the actions of the servant. This type of people has now become extinct or close to it. Those that are not extreme believe that Allaah is knowledgeable of the actions of the servant. However, they reject its occurring by His desire, ability and creating. This is what their belief is founded upon. [Source]

The following hadeeth was reported in Saheeh al-Muslim

It is narrated on the authority of Yahya b. Ya’mur that the first man who discussed qadr (Divine Decree) in Basra was Ma’bad al-Juhani. I along with Humaid b. ‘Abdur-Rahman Himyari set out for pilgrimage or for ‘Umrah and said:

Should it so happen that we come into contact with one of the Companions of the Messenger of Allah (ﷺ) we shall ask him about what is talked about  taqdir  (Divine Decree). Accidentally we came across Abdullah ibn Umar ibn al-Khattab, while he was entering the mosque. My companion and I surrounded him. One of us (stood) on his right and the other stood on his left. I expected that my companion would authorize me to speak. I therefore said:

Abu Abdur Rahman! There have appeared some people in our land who recite the Qur’an and pursue knowledge. And then after talking about their affairs, added: They (such people) claim that there is no such thing as Divine Decree and events are not predestined.

He (Abdullah ibn Umar) said:

When you happen to meet such people tell them that I have nothing to do with them and they have nothing to do with me. And verily they are in no way responsible for my (belief).

Abdullah ibn Umar swore by Him (the Lord) (and said):

If any one of them (who does not believe in the Divine Decree) had with him gold equal to the bulk of (the mountain) Uhud and spent it (in the way of Allah), Allah would not accept it unless he affirmed his faith in Divine Decree.

Sahih Muslim : Book of Faith (Book 1, Hadith 1)
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