Sayyiduna Jabir bin Abdullah (may Allah be pleased with them both) narrates that the Prophet (peace and blessings be upon him) said: "Whoever visits a sick person remains continually immersed in mercy until he sits down, and when he sits down, he plunges into it (mercy)."
Ahmad and al-Bazzar recorded it. The narrators of Ahmad are the narrators of the Sahih.
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الجنائز / 3767