It is as if he had freed one hundred slaves from the descendants of Ishmael. And whoever glorifies Allah (saying "Allahu akbar") one hundred times in the morning and one hundred times in the evening, no one on that day will come with more than what he has brought, except one who said the like of what he said, or added to what he said." (1)

This is a good and authentic (hasan gharib) hadith.

3778 - We were told by al-Husayn ibn al-Aswad al-'Ijli al-Baghdadi, who said: We were told by Yahya ibn Adam, from al-Hasan ibn Salih, from Abu Bishr, from al-Zuhri, who said: A single glorification (tasbiha) in Ramadan is better than a thousand glorifications outside of it. (2)

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(1) Al-Dahhak ibn Humra — even though he is weak — has a corroborator in al-Nasa'i, and the narration of 'Amr ibn Shu'ayb, from his father, from his grandfather, the imams concluded that it is hasan (good) when the one narrating from him is trustworthy. Nevertheless, they have objected to more than one hadith of his, and perhaps this hadith is among them. See "Siyar A'lam al-Nubala'" 5/165-180, and "Mizan al-I'tidal" 3/263-268.

It was also recorded by al-Mizzi in "Tahdhib al-Kamal" 11/110-111 via the route of Abu Sufyan al-Himyari, with this chain.

It was also recorded with similar wording by al-Nasa'i in "'Amal al-Yawm wa al-Layla" (821), and by al-Tabarani in "Musnad al-Shamiyyin" (516) via the route of al-Awza'i, from 'Amr ibn Shu'ayb, with it.

It was also recorded by al-Tabarani in "Musnad al-Shamiyyin" (517) via the route of 'Ata' ibn al-Sa'ib, from his father, from 'Abdullah ibn 'Amr. And its chain is weak.

(2) It was recorded by Ibn Shayba 10/432, and al-Mizzi in "Tahdhib al-Kamal" 33/78-79, and it is not authentic from al-Zuhri, for Abu Bishr, the one who narrates it from him, is unknown and not recognized. And Allah knows best.