Al-Matalib al-'Aliyah 2472 — The virtue of visiting the sick

It is narrated from Sayyiduna Amr bin Hazm (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) said: "Whoever goes to visit and tend a sick person continues to wade in the mercy of Allah Almighty (while going), until when he sits down with the sick person he becomes fully immersed in that mercy (as though divine mercy covers him)."
Imam Abd bin Humayd added these words in his narration, that he (peace and blessings be upon him) said: "Then when he returns after the visit, he continues to wade in divine mercy in the same way until he reaches his home, from where he had set out (for the visit)."