Customs: Shalom Aleichem before Kiddush

CUSTOMS

Why is Shalom Aleichem--"Peace unto you, angels" sung before kiddush on Friday night?

Since in the hustle and bustle of Shabbat preparations, members of the household might irritate one another, the angels are called upon to restore peace. Also, according to the Midrash, when returning home from the synagogue, we are escorted by two angels, one good and one evil. When they enter the home and see everything beautiful and serene, the good angel blesses the family, and the evil one must answer "amen."