SANDAK (Heb. סַנְדָּק; in common parlance also sandek ), designation of the godfather who holds the male child upon his knees during the *circumcision ceremony. The name is derived either from the Greek σύνδικος (cf. Lat. syndicus, "patron"), or, more probably, from σύντεκνος ("companion of the father," cf. Fr. compère; Ger. Gevatter); the form syndikos appears in post-mishnaic Midrash literature (Yal., Ps. 723).
The function of the sandak probably arose from the necessity of having someone assist the mohel by holding the child firmly during the circumcision operation. To act as sandak is considered a great honor and as a meritorious religious act which, according to the kabbalists, has atoning qualities. Where a grandfather of the child is still alive, it is customary to bestow the honor of sandak upon him. The woman who brings the child to the circumcision and hands it over to the sandak is called sandakit. The sandak is also known by various other names: ba'al berit or ba'al berit milah; tofes ha-yeled ("holder of the child"); av sheni ("second father"); or shali'aḥ ("messenger"). Jews of European origin also use the term kvater (the woman, kvaterin), which is the corrupted form of the German Gevatter ("godfather"). The question is raised whether a person may be sandak more than once in the same family. R. *Elijah b. Solomon Zalman, the Gaon of Vilna, decided in the affirmative (Be'ur ha-Gra to yd 265), notwithstanding reservations against this practice based upon fear of the "evil eye."
Kohut, Arukh, 6 (19226), 83–84; Eisenstein, Dinim, 222.