Leaving out Yigdal
Q. Why do some synagogues sing Yigdal on Friday nights and others sing Adon Olam?
A. Samson Raphael Hirsch said that Jewish beliefs were seen in the parade of the calendar.
There is an alternative if you look at Jewish songs. What a Jew sings indicates what he believes.
Yigdal illustrates this. It is based on the 13 Principles of Maimonides, but critics objected to singling out these 13 items and said that the whole of Judaism is holy and there is no justification for singling out 13 principles and giving them extra status. It is for this reason that authorities such as the Arizal (Rabbi Isaac Luria) and Siddur HaG’ra omit Yigdal.
Adon Olam is better in that it not only speaks about God philosophically but emotionally, not only saying that God is, is eternal and unique, but good, forgiving and constant.
