How authentic is the Hadith: "When Divine Decree (Qada’) is mentioned, refrain," and if it is authentic, how is that interpreted given the abundance of ancient and contemporary theological books that delve into the issue of Divine Decree and Predestination (Qadar)?

The Hadith (definition): "When divine decree (Al-Qadar (definition)) is mentioned, refrain (from discussing it)" is authentic. The meaning of "refraining" is to avoid over-exerting oneself in comprehending the secret of divine decree, to refrain from debating with those who deny it, and to avoid delving into it with one's intellect. This is because divine decree is Allah Almighty's secret among His creation; neither a close angel nor a sent prophet knows it. Delving deeply into it is a cause for being forsaken. Its knowledge is concealed from creation, as Allah Almighty says: "He is not questioned about what He does, but they will be questioned." And whoever asks "Why did He do it?" has rejected the ruling of the Book and is therefore among the disbelievers. The Ahlus Sunnah (definition) are unanimous in believing in divine decree and refraining from argumentation regarding it. However, the discourse of scholars concerning it is permissible to clarify the correct doctrine and refute misconceptions.