Question: If there is no levi in Shul should the kohanim wash their own hands?
Introduction: The Zohar (Parshas Noso 146b) writes that a kohen should endeavour to “add kedusha to his kedusha” before birkas kohanim which the Zohar explains to mean that he should have his hands washed by an individual who “is kodosh” i.e. a levi.
The Beis Yosef (Orach Chayim Siman 128) writes that he heard that the custom in Spain was that the leviyim would wash the hands of the Kohanim. The Beis Yosef writes that he wondered what the source of this minhag was until he found the aforementioned Zohar.
The Shulchan Aruch (Orach Chayim Siman 128 Se’if 6) writes that a levi should wash the hands of the kohanim, and prior to this the levi should wash his own hands.
Discussion: The Bach writes in the name of the Maharil that if no levi is present, a bechor (firstborn) should wash the kohanim’s hands. The Bach explains that this is because a firstborn is also “kodosh”, and that we are discussing a firstborn who is a firstborn to his mother [i.e. irrespective of whether he is a firstborn to his father or not].
The Taz (s.k. 3) and Magen Avraham (s.k. 7) both quote this Bach. The Mishna Berura (s.k. 22) also writes that when no levi is present a bechor who is a firstborn to his mother should wash the kohanim’s hands “because he is also considered kodosh”, and if no bechor is present it is preferable that the kohen washes his own hands instead of a yisroel washing the hands of the kohen.
It appears from the Magen Avraham and Machtzis Hashekel that only a bechor who would require pidyon haben is eligible to wash the kohanim’s hands. I.e., a bechor delivered via Caesarean section or a bechor born after a miscarriage who are both not subject to pidyon haben (the latter with a brocho) would both not be eligible to wash the kohanim’s hands because they are both not “peter rechem” and therefore not subject to the extra kedusha required to be eligible to wash the hands of the kohen.
The source for this Mishna Berura appears to be from the Sheyorei Knesses Hagedolah who writes clearly that if no levi or bechor is present, it is preferable that the kohanim wash their own hands, rather than a yisroel washing the hands of the kohen. This is based on the Zohar that writes that the kohen should have his hands washed by an individual who is “kodosh”..
The Kaf Hachayim (s.k. 40) writes that he has not observed bechorim washing the kohanim’s hands [even when no leviyim are present]. The Kaf Hachayim explains that it appears that the minhag is based on the Zohar which only mentions leviyim [and not bechorim] and if no levi is present the kohen should wash his hands himself.
Presumably, those who require a levi to wash his own hands before washing the kohen’s hands would also require a bechor to do so.
Conclusion: Ideally, the Shulchan Aruch writes that a levi should wash the hands of the kohanim prior to birkas kohanim.
The Bach writes in the name of the Maharil that if no levi is present, a bechor (firstborn) should wash the kohanim’s hands, because a firstborn is also “kodosh”. According to the Bach this only applies to a firstborn who is a firstborn to his mother.
It appears from the Magen Avraham and Machtzis Hashekel that only a bechor who would require pidyon haben is eligible to wash the kohanim’s hands. I.e., a bechor delivered via Caesarean section or a bechor born after a miscarriage who are both not subject to pidyon haben with a brocho would both not be eligible to wash the kohanim’s hands.
The Taz and Magen Avraham both quote the Bach. The Mishna Berura also writes that when no levi is present a bechor (who is a firstborn to his mother) should wash the kohanim’s hands. The Kaf Hachayim writes that he has not observed bechorim washing the kohanim’s hands.
If no bechor is present it is preferable that the kohen washes his own hands, rather than a yisroel washing the hands of the kohen.