The etiquettes of greeting
The Islamic etiquettes of greeting one other emphasise:
Muslims greeting (and saying farewell to) one another with "salaam" as an integral part of faith - regardless of whether the people know each other or not
Muslims greeting one another with "Assalamu 'alaykum" (Peace be upon you) and replying with "wa alaykum us salaam" (and peace be upon you also)
Replying to a Non-Muslim's greeting of "salaam" with "wa alaykum" (and you)
Fostering love and brotherhood and sisterhood
Adhering to the limits Allah has ordained with regard to not shaking hands or being too friendly with the opposite sex (unless closely related)
Being pleased to see one another and speaking nicely
Hugging and kissing on the cheek
What a Muslim should do when greeting another Muslim
Muslims should not greet each other with "Hi" or "Good morning" or a mere wave, because Allah has commanded Muslims to greet each other in a prescribed manner.
Whenever a Muslim meets another Muslim, whether they know them or not, they should say:
(Peace be upon you)
In reply, the other person should say:
"wa alaykum us salaam"
(and Peace be upon you also)
Note: It is preferable to add "wa rahmatullah" (and the mercy of Allah) to the end of either of the above. It is better still to add "wa rahmatullahi wa barakatuhu" (and the mercy and blessings of Allah) to the end of either of the above greetings.
A person should also reply to the "salaam" to at least the same "degree" or better. For example, if a person was to say "Assalamu 'alaykum wa rahmatullah", the best reply would be "wa 'alaykum us salaam wa rahmatullahi wa barakatuhu" (although just "wa 'alaykum us salaam wa rahmatullah" would be acceptable).
Allah says in the Qur'an:
"When you are greeted with a greeting, greet in return with that what is better than it, or (at least) return it equally"
In addition to this, upon greeting each other Muslims should:
Shake or clasp hands. Prophet Muhammad has been recorded as saying:
"When two Muslims meet and shake hands, they are forgiven their sins before they part with each other"
Note: this only applies to men greeting men, women greeting women, or women and men who are closely related (to whom marriage is permanently forbidden) greeting each other. It is not permissible for men and women who don't fall into this category to shake hands because Prophet Muhammad (PBUH) never touched the hand of a woman who was lawful to him (they would give their oath of allegiance verbally) and he said:
"For one of you to be stabbed in the head with an iron needle is better for him than that he should touch a woman who is not permissible for him."
"I do not shake hands with women."
Smile and put on a pleasant face (same rulings as for shaking hands with regard to greeting the opposite sex - only allowed if closely related). Prophet Muhammad (PBUH) said:
"Protect yourselves from the fire of Hell, even if it be by spending only half a date as alms; and one who does not get even that, should at least speak nicely"
"Even utterance of nice words is charity"
"Do not consider even the smallest good deed as insignificant; even meeting your brother (in faith) with a cheerful face (is a good deed)"
Embrace and kiss on the cheek one's child (to show love for him/her). Note: Kissing another person on the mouth is only allowed between husband and wife.
The importance of saying "salaam"
Greeting one another with "salaam" (i.e. saying Assalamu 'alaykum and its reply), is something of great importance in Islam, as the following quotes from Prophet Muhammad (PBUH) illustrate:
"There are three things which if brought together constitute Iman (faith): justice with oneself, greeting people with greetings of salaam, and freeing oneself from stinginess"
'A man came to Prophet Muhammad (PBUH) and asked him "What is the best act of a Muslim?". He said "To feed others and to give greetings of salaam to those you know and those whom you do not know"'
"You shall not enter paradise until you believe, and you have not believed until you love one another. Shall I tell you of something you can do to love one another? Give one another frequent greetings of salaam."
"The Muslim has five rights over his fellow-Muslim: he should return his salaams, visit him when he is sick, attend his funeral, accept his invitation, and pray for mercy for him [say "Yarhamuk Allah"] when he sneezes."
Even if a person is angry with someone (in which case it is more reason to offer salaam), or think that the other person will not return his/her salaam, they should still offer it. If a person is offered salaam then they are obliged to reply. It is not permissible for a Muslim to purposely go more than three days without speaking to another Muslim due to bad feelings, or the like.
Among the reasons why greeting with salaam is so important are:
It is something distinctive for the Muslims to greet each other with
It sows seeds of love, brotherhood / sisterhood, friendship and unites the Muslims together with a sense of security and common purpose
It helps dispel any bad feelings or hostility and forces people who may try to ignore one another or not speak to another, to do so
What does "salaam" mean?
"Salaam" literally means "peace" (which is where the word 'Islam' also comes from). In a broader sense "salaam" means harmlessness, safety and protection from evil and from faults. As-Salaam is one of the Names of Allah, and so when one says "salaam", they are in effect saying: "May the blessing of His name descend upon you".
Who should say salaam first?
A person should hasten to be the first to offer salaam to the other person, since there is great reward in this. The following general rules also apply:
the smaller group should offer salaam to the larger group
the younger person should offer salaam to the older person
the person walking or riding should offer salaam to the sitting person
How Non-Muslims should be greeted
If a Non-Muslim says "Assalamu 'alaykum" to a Muslim, the Muslim should reply:
(and to you)
What to say when leaving
When leaving, a person should also offer salaam, since the greeting is no more important than the farewell. The Messenger of Allah (PBUH) said:
"When one of you joins a gathering, let him say salaam. When he wants to get up and leave, let him say salaam. The former is not more important than the latter."