Q. Why don’t the kohanim duchan (or duchen) in synagogue every day in the Diaspora like they do in Israel?
A. The kohanim blessed the people from a platform in the Temple known as a duchan, hence the word duchaning to describe the ceremony. In Israel people are used to daily duchaning; in the Diaspora it generally takes place only on festivals. Reasons include the following:
• The kohen must be ritually pure when he duchans, and there is more likelihood of this on festivals.
• The festival prayers say, “Bestow on us the blessing of Your festivals”, which suggests a link between festivals and blessing.
• The kohanim have to bless the people with joy, and festivals evoke this emotion since the Torah says, v’samachta b’chaggecha – “you shall rejoice on your festival”. Why can there not be joy every day in the Diaspora? Because it was often a bitter experience to be a Diaspora Jew.
Some advocate duchaning when a festival falls on Shabbat, especially Yom Kippur. Some, especially Sephardim, duchan every Shabbat, though Ashkenazim note that people’s joy tends to be affected on Shabbat by thoughts of the problems which they will face next day. There is the further concern that some of those who claim to be kohanim may be in error. Jews in the Diaspora were often confused about their lineage, whereas in Israel greater care was exercised.
Rabbi Nathan Adler had thoroughly researched his kohanic background and duchaned every day. The Vilna Gaon wanted to institute daily duchaning but was unable to change the accepted practice. The Ba’al HaTanya, the teacher of Chabad Chassidism, also saw no real reason not to duchan daily.