Is "Whoever issues a fatwa without knowledge has disbelieved" a noble Prophetic Hadith, or a saying uttered on a certain occasion?

We have not found a text that states that one who issues a fatwa without knowledge commits major disbelief (kufr akbar) that expels him from the fold of Islam. Issuing a fatwa without knowledge is one of the gravest sins and greatest transgressions, for it is speaking about Allah without knowledge, which the Quran associates with polytheism (shirk). Allah Almighty says: {And do not say about what your tongues falsely describe, "This is lawful and this is unlawful," to invent a lie against Allah. Indeed, those who invent a lie against Allah will not succeed.} Its danger extends beyond the individual to society, corrupting and misleading it. The Prophet, peace and blessings be upon him, said: "They gave fatwas without knowledge, so they went astray and led others astray." The sin of the one who gives a fatwa without knowledge falls upon the one for whom the fatwa was given. The righteous predecessors were hesitant to issue fatwas due to their seriousness.