Pidyon haben,like brit milah, circumcision, is primarily the responsibility of the father. A brit milah must be performed on the eighth day of the child’s birth, unless it would endanger the life of the child to do so. Pidyon haben must be performed on the thirty-first day of the child’s birth. Neither ceremony may be delayed beyond its prescribed time unless there is some halachic justification to do so.
In the case of milah, such a delay is a very serious matter since the punishment for unjustifiably delaying circumcision, by even one day, is karet, premature death at the hand of God. So important is the duty to circumcise on the eighth day, the milah is performed even if the eighth day happens to be on Shabbat – even though the surgery involves a melachah de’oraita, biblically prohibited work on Shabbat. Accordingly, in the event of a conflict between the duty to circumcise on the eighth day and the prohibition against violating the Shabbat by inflicting a wound, the duty to circumcise takes precedence.
It is also most important that a devoutly observant Jew perform the circumcision. So important is this requirement that it takes precedence over the requirement to circumcise on the eighth day. Accordingly, if the only person available to perform the milah on the eighth day is a person who is not an observant Jew, the milah should be postponed until a devout mohel is available.
Unlike a brit milah on the eighth day, which overrides the prohibition of performing a melachah on Shabbat, a pidyon haben, which involves the handling of money and the performance of a transaction – both prohibited activities on Shabbat – does not override the observance of Shabbat. Accordingly, if the thirty-first day of the birth is on Shabbat, the pidyon haben is postponed to Sunday. Apart from this situation, there is generally no license to postpone the pidyon haben ceremony beyond its prescribed time. Such a postponement, although not as egregious as the postponement of a brit milah, would violate the general prohibition of shihui mitzvah, postponing the performance of a mitzvah.
Both the brit milah and the pidyon haben ceremonies are celebrated by a seudat mitzvah, a festive meal to which family and friends are invited. If the thirty-first day is in the middle of the week, it would of course be more convenient to postpone the pidyon haben ceremony and festivities to Sunday when more guests can attend. Such a postponement is, however, unacceptable for the reasons articulated above.
In a situation where the eighth day is in the middle of the week but the parents insist that a brit milah be held on a Sunday and threaten to have a non-observant doctor perform the circumcision if the observant mohel does not agree to the postponement, then, according Rabbi Moshe Feinstein, it is better for the observant mohel to perform the circumcision on Sunday, even though this results in a prohibited delay, rather than risk the circumcision will be performed by a non-observant doctor. The reason for this is that a circumcision performed by a non-observant person is ineffective.
Similarly, if the parents insist that the pidyon haben be postponed to a Sunday when more people can attend the seudah, then, notwithstanding the violation of the general prohibition of shihui mitzvah, the kohen may perform the ceremony, even though it is beyond the thirty-first day. Of course, in both situations, but especially in the milah situation, the parents should be prevailed upon to conduct the ceremony and the celebration at the prescribed time without any postponement.
Both the seudah in honor of the brit milah and the seudah in honor of the pidyon haben have the halachic status of festive meals, seudat mitzvah. This status has practical consequences, particularly in the period of the nine days between Rosh Chodesh Av, the first day of the month of Av, and Tisha B’Av, the ninth day of the month of Av. Accordingly, even though one should refrain from reciting the blessing of Shehecheyanuduring the nine days, this blessing may be recited for a pidyon haben performed during this time. Similarly, although one is not permitted to eat meat or drink wine during the nine days, close family and friends of the child’s family may do so at a brit or pidyon haben seudah during this time, even onErev Tisha B’Av, the day preceding Tisha B’Av, provided it is done before noon.