The Book of Virtue, Enjoining Good Manners, and Joining of the Ties of Kinship
حَدَّثَنَا يَحْيَى بْنُ يَحْيَى التَّمِيمِيُّ، أَخْبَرَنَا هُشَيْمٌ، عَنْ خَالِدٍ، عَنْ أَبِي قِلاَبَةَ، عَنْ أَبِي، أَسْمَاءَ عَنْ ثَوْبَانَ، مَوْلَى رَسُولِ اللَّهِ صلى الله عليه وسلم قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " مَنْ عَادَ مَرِيضًا لَمْ يَزَلْ فِي خُرْفَةِ الْجَنَّةِ حَتَّى يَرْجِعَ " .Thauban, the freed slave of Allah's Messenger (ﷺ), reported that Allah's Messenger (ﷺ) said:He who visits the sick continues to remain in the fruit garden of Paradise until he returns
From Sahih Muslim, whose reports the scholars accept as authentic.