The Book of Divine Unity · Hadith 554 (#Ḥadīth #14)
Chapter 67 | The Prohibition of Discussing, Debating, and Arguing about Allah
14 - وبهذا الإسناد، عن أبي اليسع، عن سليمان بن خالد، قال: قال أبو عبد الله عليه السلام: إياكم والتفكر في الله فإن التفكر في الله لا يزيد إلا تيها لأن الله عز وجل لا تدركه الأبصار ولا يوصف بمقدار.
14. And with the same chain of transmission, on the authority of Abu al-Yas`, on the authority of Sulayman ibn Khalid that Abu `Abd Allah al-Sadiq said: ”Be ware of speculation about Allah. Verily, speculation about Allah does nothing but lead astray. Allah, the Mighty and high, cannot be perceived by vision, and He cannot be attributed with measure.”
Gradings are classical jarḥ-wa-taʿdīl, name-matched to a rijāl index (not individually re-verified).