The Messenger of Allah ﷺ said, "In Paradise there is a chamber whose outside can be seen from within and whose inside can be seen from without. Allah has prepared it for those who feed others, speak gently, fast regularly, and pray at night while people sleep."
قال رسول الله ﷺ: إن في الجنة غرفة يرى ظاهرها من باطنها، وباطنها من ظاهرها، أعده الله لمن أطعم الطعام، وألآن الكلام، وتابع الصيام، وصلى والناس نيام.
Ahmad (22905) and Tabarani in Al-Kabir (3466) both narrated it through Abdul-Razzaq (it is also in his Musannaf, 20883) from Mamar, from Yahya bin Abu Kathir, from Ibn Maaniq or Abu Maaniq, from Abu Malik Ashari, who related it.Through this same route, Ibn Khuzayma (2137) and Ibn Hibban (509) also narrated it in their two Sahihs, except that Ibn Hibban added to the hadith, "and spread the greeting of peace," and did not mention "fasting," which is not in Abdul-Razzaq's version. Likewise, his version does not contain "soften your speech." It appears this comes down to differences between the manuscript copies.Its chain of transmission is hasan because of Ibn Maaniq, who is Abdullah bin Maaniq Ashari, as Abu Hatim stated following the hadith. His kunya is Abu Maaniq. Ibn Hibban and Ajli both deemed him trustworthy, and he belongs to the generation of Syrian successors. Abu Malik Ashari was a companion of the Prophet, his name being Harith bin Harith, and he too was Syrian. So it is entirely possible that the two of them met, and whoever rules this out has strayed from the truth.Haythami said in Al-Majmu, "Tabarani narrated it in Al-Kabir, and its narrators are trustworthy," but he failed to also attribute it to Ahmad.As for Ibn Khuzayma's statement, "I do not know Ibn Maaniq, nor Abu Maaniq, from whom Yahya bin Abu Kathir narrated," others besides him did know him.