Pirkei Shirah. With Kabbalistic commentaries Siach Yitzchak and Sha’ar Shimon by two brothers,Yitzchak and Shimon Wolf ben Meir Nikolsburg of Prague

Perek Shirah is an extremely ancient composition thought to be part of the corpus of second-century Hechalot literature. In Perek Shirah each animal is assigned a verse from the Bible which it utters in praise of the Creator. See EJ, Vol. XIII, cols. 273-5. In the approbations to this edition, the rabbis of Venice, Mantua, Verona have only superlative praise for both brothers and their work. R. Moshe Zacuto, the leading contemporary Italian kabbalist, was especially effusive in his praise, titling R. Yitzchak, “sover ha-razim...mekubal, he-Chasid (explainer of secrets...the pious kabbalist).” In the commentary Sha’ar Shimon (f.14r.) there is a discussion of the holy name “Ke-DaT” written on the forehead of Messiah son of David. The origin of this motif is R. Samson of Ostropolia, martyred in the Chmielnicki massacres of 1648. See Y. Liebes, Mysticism and Reality in: Twersky and Septimus (eds.) Jewish Thought in the Seventeenth Century (1987) p. 226