The Ben Ish Hai (Rav Yosef Haim of Baghdad, 1833-1909), in his work Rab Pe’alim (vol. 2, Y.D. 35), writes that it is not only permissible for a father to serve as the Sandak at his own son’s Berit, but also recommended. By holding the baby and enabling the Mohel to perform the circumcision, the Ben Ish Hai says, the Sandak is considered as having personally performed the Misva of Mila. The Gemara in Masechet Makkot establishes that if a barber removes somebody’s Pe’ot (sideburns), then both the barber and the customer have transgressed the Torah violation. The customer participated in the sinful act by moving his head and enabling the barber to remove the Pe’ot, and thus he, too, is considered as having committed the transgression. The Ben Ish Hai claims that this is true with regard to Misvot, as well. The Sandak enables the Mohel to circumcise the infant, and thus he is considered as having performed the Misva. Hence, as there is value in personally performing the Mila of one’s own son, it is recommended – at least according to the Ben Ish Hai – that a father serve as the Sandak at his son’s Berit in order to receive credit for having actually performed the Mila.
