Allah's Messenger (ﷺ) said: "Verily! Allah has ninety-nine Names concerning which he who retains them in his memory will enter Paradise." [Agreed upon]. at-Tirmidhi and Ibn Hibban listed the Names. However, investigations show that their listing is Idraj (an insertion) from one of the narrators [not from the words of the Prophet].
Hadith Commentary: The Ninety-Nine Names of Allah
This noble hadith from Sahih al-Bukhari and Sahih Muslim establishes the immense virtue of learning and preserving the ninety-nine Names of Allah. The phrase "he who retains them in his memory" encompasses both memorization and understanding their meanings, acting upon their implications, and calling upon Allah through them.
The scholars clarify that entering Paradise through this means does not negate the necessity of faith and righteous deeds, but rather indicates that proper comprehension of Allah's Names leads to sincere worship and thus to Paradise. Each Name inspires specific worship: knowing al-Ghafur (The All-Forgiving) leads to seeking forgiveness; knowing ar-Razzaq (The Provider) leads to trusting in His provision.
Concerning the specific listing mentioned by at-Tirmidhi and Ibn Hibban, the scholars of hadith have determined this to be idraj (insertion) from the narrators rather than the Prophet's own words. Therefore, while the names listed are authentically Allah's Names, their compilation in that particular format is not established as a prophetic tradition. The wisdom in this is that Muslims remain open to discovering all of Allah's Names throughout the Quran and Sunnah without restriction to a fixed list.