Allah the Exalted said:
١٣٥ - باب استحباب السلام إذا دخل بيته
Allah the Exalted said:
There is not upon the blind [any] constraint nor upon the lame constraint nor upon the ill constraint nor upon yourselves when you eat from your [own] houses or the houses of your fathers or the houses of your mothers or the houses of your brothers or the houses of your sisters or the houses of your father's brothers or the houses of your father's sisters or the houses of your mother's brothers or the houses of your mother's sisters or [from houses] whose keys you possess or [from the house] of your friend. There is no blame upon you whether you eat together or separately. But when you enter houses, give greetings of peace1 upon each other - a greeting from Allāh, blessed and good. Thus does Allāh make clear to you the verses [of ordinance] that you may understand.
Anas (may Allah be pleased with him) reported: The Messenger of Allah (peace and blessings be upon him) said to me: "O my dear son, when you enter upon your family, give the greeting of peace; it will be a blessing upon you and upon the people of your household." Narrated by al-Tirmidhī, who said: "A good and sound hadith (ḥasan ṣaḥīḥ)."