📋 Some notes on the general etiquettes of greeting with the salaam:
1] Initiating greeting with the salaam is a rewarding Sunnah. If you say the salaam upon entering a Masjid, lecture hall, room, office or classroom,
you will Inn-sha-Allah receive rewards for saying salaam. If you choose to enter quietly without any salaam, there is no penalty or punishment.
2] Answering a Muslim's salaam is waajib/obligatory, since Allah the Almighty Himself commands the believers in Surah An-Nisaa that when we are greeted with the salaam, we should greet with a better greeting (say "wa 'alaikum as-salaam wa Rahmatullahi wa Barakatuh") or at least return it.
3] It is closer to the Sunnah and tradition of the beloved Messenger Muhammad SallAllahu 'alaihi wa sallam for: The younger Muslim to first greet the older Muslim, the driver (in a vehicle) to first greet the person walking, the individual walking to first greet those who are already seated, and a small group to first greet a much larger group. This encourages a sense of humility, self-respect, and prevents one from treating others as though they are celebrities who feel entitled to be greeted first due to their social status.
4] All actions are rewarded according to the doer's niyyah/intention. It is wiser to avoid greeting non-mahrams of the opposite gender if doing so regularly could lead to fitna or trigger gradual feelings of attraction.
5] While it is encouraged to say the salaam upon entering a circle or meeting, it is more important, and from proper Islamic manners, to say the salaam again before one leaves the gathering instead of abruptly disappearing without notification.
6] When some non-Muslims greet you with "as-salaamu 'alaikum", you may respond equally with "wa 'alaikum as-salaam". The response "wa 'alaikum" which the noble Prophet Muhammad SallAllahu 'alaihi wa sallam told a number of Jews on one occasion was said to answer their statement "as-saam 'alaikum". If a non-Muslim tries to greet you in a passive-aggressive way, you may answer back with "wa 'alaikum" meaning "and upon you too".
7] Don't feel offended if some individuals purposely ignore your salaam. There are Angels and Muslim jinn around you who may have answered your greeting, and
Inn-sha-Allah you'll be rewarded for having the courage to initiate salaams.
Allah the Almighty knows best.
~•~
📖 Abu Umamah RadhiAllahu 'anhu narrated: Allah's noble Messenger Muhammad SallAllahu 'alaihi wa sallam said, "Verily, the best people to Allah are those who are the first to greet with peace."
Source: Sunan Abī Dāwūd 5197
Grade: Sahih (Authentic) according to Al-Albani
📖 Abu Huraira RadhiAllahu 'anhu narrated: Allah's noble Messenger Muhammad SallAllahu 'alaihi wa sallam said, "When one of you arrives in a gathering, let him greet them with peace. When he intends to leave, let him depart with greetings of peace. The first greeting is not more worthy than the last."
Source: Sunan Abī Dāwūd 5208
Grade: Sahih (Authentic) according to Al-Arna’ut
📖 Abu Huraira RadhiAllahu 'anhu narrated: Allah's noble Messenger Muhammad SallAllahu 'alaihi wa sallam said, "The rider should greet with peace those who are walking, those who are walking should greet those who are sitting, and a small group should greet a larger group."
Source: Sahih Al-Bukhari 5880
Sahih Muslim 2160
Grade: Muttafaqun Alayhi (Authenticity agreed upon) according to Al-Bukhari and Muslim
https://abdurrahman.org/category/islam/greetings-salams/
https://binbaz.org.sa/fatwas/13513/%D8%AD%D9%83%D9%85-%D9%85%D9%86-%D9%84%D8%A7-%D9%8A%D8%B1%D8%AF-%D8%A7%D9%84%D8%B3%D9%84%D8%A7%D9%85-%D8%B9%D9%84%D9%89-%D9%85%D9%86-%D9%8A%D8%B3%D9%84%D9%85-%D8%B9%D9%84%D9%8A%D9%87