Shalom aleichem

Shalom aleichem is a greeting in the Hebrew language. When someone is greeted with these words, the appropriate response is . The term is plural, but is still used when addressing one person.
This form of greeting is traditional among Jews worldwide, and typically connotes a religious context. It is particularly common among Ashkenazi Jews.
History
Biblical
In the Hebrew Bible, various characters use the greeting shalom, in the form (masculine singular) or (plural).
The term (masculine singular) is first attested in the Scroll of Blessings for the First Month (before 30 BCE), a Dead Sea Scroll, where it is spelled, in their manner, with a final he.
The plural first appears in the Jerusalem Talmud, always with a plural object. It occurs there six times and the response is to repeat .
appears many times in the Talmud Bavli, where the response is to repeat .
The inverted response (masculine singular) is first attested in the Midrash Abba Gorion (before 1050 CE), in the gloss on Esther 3:5:
"What did Haman do when he passed by and Mordechai did not rise to greet him? He came from one side and made as if Mordechai had greeted him, saying 'ʿālēkā šālōm,' but Mordechai replied, 'the LORD says there is no šālōm for the wicked.'" —
The plural greeting and response became common among Ashkenazi Jews in the second half of the next millennium, as the use of plural forms to denote respect was imported from French and German.
In other languages
Many other Semitic languages (the language family to which Hebrew belongs), as well as some Indo-European languages, share cognates to this greeting.
Semitic languages
Among Arabs, the variation has been a traditional greeting since antiquity, with the appropriate response being . Following the early Muslim conquests in the 7th century, it was established as a prevalent greeting among many non-Arab Muslims.
In Aramaic and Classic Syriac, the term is prevalent.
Indo-European languages
Similar greetings gained prominence with the rise of European Christianity. Within the Catholic Church and the Eastern Orthodox Church, bishops and priests initially use the liturgical greeting "peace be with you" during divine services. During the Mass, Catholic priests who are not bishops say "the Lord be with you", with "and with your spirit" being the appropriate response. Bishops and priests also use the somewhat similar greeting "the peace of the Lord be with you always" during the Mass. In the Orthodox Church, the greeting is always "peace be with you" during services.
Similarly, "peace be with you" is used within Anglicanism, particularly within the liturgies of the Episcopal Church and others in the Anglican Communion, with the "and also with you" being the appropriate response. In the liturgy of the Lutheran Church, the greeting by the pastor is "the peace of Christ be with you always" followed by "and also with you" as the congregation's response. Others, such as the Presbyterian Church and the Church of the Brethren, have similar traditional greetings.
Jewish/Israeli songs
The greeting inspired the traditional folk song Hevenu Shalom Aleichem, which was eventually translated to many languages and became popular in peace demonstrations abroad.
See also
Shalom, the Hebrew greeting for "peace"
As-salamu alaykum, the Arabic greeting
References
Greeting words and phrases
Hebrew words and phrases
Judaism and peace