Book: Siyar A'lam An-Nubala by Ad-Dhahabi - سير أعلام النبلاء ـ الإمام الذهبي

In His Work "Al-Siyar" Volume 9 (284):

In the two Sahih collections, there are a few hadiths within the "Musnad". However, it can be said that these are not refutations of their sayings, as the Muslims have not disputed over them, and this claim does not imply that what is found in it should be a proof. Therein are a number of weak hadiths that may be transmitted but should not be used as evidence. Additionally, within it are a few hadiths of dubious authenticity, yet they are but a drop in the ocean, amidst numerous additional contributions by Abdullah ibn Ahmad.

Al-Hafiz's Commentary in "Al-Siyar" Volume 14 (276):

The book "Ihya Ulum al-Din" by Abu Hamid al-Ghazali contains a number of false hadiths. However, it also contains much good, were it not for the inclusion of customs, formalities, and unusual tales of ascetics from wise men and deviant Sufis. We ask Allah for beneficial knowledge. Do you know what beneficial knowledge is? It is that which the Quran revealed and the Messenger ﷺ explained by word and deed, without any prohibition. He (﵊) said, "Whoever turns away from my Sunnah is not of me" [1]. So, my brother, adhere to contemplating the Book of Allah, continuously reading "Sahihain", "Sunan al-Nasa'i", "Riyadh al-Nawawi", and "Adhkar", and you will prosper and succeed. Beware the views of the philosophers, tasks of ascetics, monks' hunger, and the random speeches of those secluding themselves. For all good lies in following the pure and easy monotheistic way. O, our refuge is with Allah. O Allah, guide us to Your straight path.

Continuing in "Al-Siyar" Volume 14 (277):

Abu al-Faraj ibn al-Jawzi stated: Abu Hamid authored the "Ihya" and filled it with false hadiths without realizing their falsehood. He spoke of unveiling and deviated from the principles of jurisprudence. He claimed that the stars, moon, and sun seen by Ibrahim were divine lights, not the known celestial bodies! This resembles the sayings of the esoteric sects. Ibn al-Jawzi refuted Abu Hamid in his book "Ihya", pointing out errors in several volumes, which he entitled "Al-Ahya".

In "Al-Siyar" Volume 12 (187):

I read in the handwriting of Al-Hafiz al-Diya a draft commenting on the book of Ibn Hibban where he mentioned a hadith narrated by Anas...