The Messenger of Allah ﷺ said, "A person will not truly believe until he believes in divine decree, both its good and its evil."Abu Hazim said, "May Allah curse a religion that is younger than I am," meaning the denial of divine decree.
حدثنا أنس بن عياض حدثنا أبو حازم
أن رسول الله ﷺ قال لا يؤمن المرء حتى يؤمن بالقدر خيره وشره قال أبو حازم لعن الله دينا أنا أكبر منه يعني التكذيب بالقدر
Its chain of transmission is sahih. Imam Ahmad also narrated it in Kitab al-Sunnah (p. 122) with this same chain. Abu Bakr Ajurri narrated it in Kitab al-Shariah (p. 188) with two chains, one from Firyabi from Qutayba bin Saeed from Yaqub bin Abdul-Rahman from Abu Hazim from Amr bin Shuayb, and the other from Firyabi from Qutayba from Ibn Lahia from Amr bin Shuayb, without narrating Abu Hazim's statement. Both chains are sahih. Yaqub bin Abdul-Rahman bin Muhammad Qari is trustworthy, Ahmad and Ibn Main and others declared him trustworthy, and Bukhari gave his biography in his Tarikh al-Kabir, 4/2/398.I did not find this hadith in Majma al-Zawaid, though perhaps it is there in a place hidden from me. As for Abu Hazim's statement, he means by it that the one who denies divine decree claims for himself an act of creation, when he himself is created and fashioned, and he can never have power over anything except through the strength Allah has placed within him and the circumstances and means that Allah has surrounded him with, all of which are Allah's own making and decree. It is as though he claims to be greater than Allah, as is the way of atheists and arrogant tyrants.