If the Sefer Torah is open and the Kohen is reciting the Shema he may not desist and an Israelite is called instead of him. Note: The same applies on the public fast days after Pesaĥ and Sukkot, when Vayeĥal is read: if the Kohen is not fasting an Israelite is called, and it would be best if the Kohen leaves the synagogue [Rabbi Yosef Kolon #9].
1:
We have established that it is the duty of a Kohen who is present in the synagogue to exercise his right to be the first to be called to the Torah. However, what happens if there is only one Kohen present in the synagogue and at the time that the congregation is ready to read the Torah that Kohen is prevented by halakhah from accepting the honour? Possibly one would think that the congregation should wait until the Kohen is able to accept the honour; but to do so would constitute what is called "
Tirĥa de-Tzibbura" – an unnecessary imposition on the congregation. This is why we do not wait until the Kohen has finished what he is doing, but proceed to the Torah Reading without a break.
2:
Our present halakhah refers to a situation in which the Sefer Torah has already been taken from the Ark, has been placed on the "Tevah", the Reading Desk, and has been opened at the appropriate place in readiness for the reading to begin. But the same would apply even if the Torah has not yet been taken out of the Ark. If the congregation has reached the point where there Ark is to be opened and the Torah taken out, the service should continue without interruption even if this means that there will be no Kohen available to be the first to read because he is otherwise legitimately occupied.
3:
Our present halakhah gives the example of a Kohen who is occupied with his recitation of the Shema. Possibly he arrived late for the service and although the rest of the congregation is well past this part of the service he has not yet caught up with them. (Let us note parenthetically that when one arrives late to the synagogue one does not automatically start joining in wherever the congregation happens to be, but there are certain parts of the service which may have come before which it is one's duty to complete before joining in public prayer.) The Shema must be recited with great concentration and should not be interrupted if at all possible. Halakhah does define what might constitute legitimate reasons for interrupting the reading, but this need not concern us here: the duty to recite the Shema with appropriate concentration is of Torah origin ("mi-de-orayta"), and this can hardly be said of the privilege of the Kohen to be called first to the Torah, which is only to 'prevent arguments' as it were, as we have seen. If this is the case as regards the Shema, where interruptions might be permitted in certain circumstances, it is obviously all the more so in the case of the Amidah whose recitation should not be interrupted for any reason at all and for which one should summon up all possible concentration.
4:
This is the reason why a Kohen who is legitimately occupied with some other part of the liturgy may not be called to the Torah if he is involved with passages that require concerted concentration. It may come as a surprise to some that the Shulĥan Arukh states that when this is the situation an Israelite is to be called instead of the Kohen. I say that it may be a surprise since many people think that if there is no Kohen available a Levite should be called in his place, and this is not the case. Paragraph 135:3 stated: "A Kohen reads from the Torah first, after him a Levi and after him an Israel." So, the erroneous thought goes, is it not logical that if there is no Kohen and there is a Levite that the latter should replace the Kohen as being the first to be called to the reading? However, the rights and privileges of the Levite in this matter are entirely dependent on the rights and privileges of the Kohen. If a Kohen exercises his right and privilege to be called first to the Torah then any Levite present in the synagogue has the right to be called after him. But if there is no Kohen then the Levite loses his precedence as well. In the Gemara [Gittin 59b] we read:
Abayyé says that we proceed as follows: if there is no Kohen present in the synagogue the package has broken open.
Thus these rights and privileges are a kind of "package deal" and if there is no Kohen the package breaks up. (Even though the Levite loses his right to be called before an Israelite that does not mean that he cannot be called first if that is the pleasure of the Gabbai: while he now has no greater right than an Israelite he certainly has no lesser right and all are considered to be equal.)
5:
The Rema (Rabbi Mosheh Isserles) now brings another situation in which a Kohen might not exercise his right. According to this situation he is present in the synagogue and not otherwise occupied. The situation is one where the portion being read from the Torah is a special one that is read on fast days. The Rema gives the example of a fast day in which a Kohen might not have any compunctions about publicly admitting that he is not fasting (and therefore it would be inapproriate to call him to this special reading). It was customary to fast on the Monday, Thursday and Monday following the festivals of Pesaĥ and Sukkot. These supererogatory fast days were based on what is related about the biblical Job [1:5] who would make expiation after his family had celebrated – in case they might have sinned during the celebration! These fast days were not universally observed even in earlier times, and I would be very surprised if there is even one Conservative congregation in modern times where they are observed.
6:
If, on a fast day, there is no Kohen available who is fasting, an Israelite (or Levite) who is fasting should be called to the Torah. The Rema (basing himself on Maharik) suggests that in such circumstances it would be best if non-fasting priests were to temporarily leave the sanctuary. This is so that people will not think that this person was not called either because he is not a Kohen or because he is a Kohen but labours under some ritual disqualification.
7:
Maharik is the acronym which identifies Rabbi Yosef Kolon. Rabbi Kolon was born in 1420, lived in Italy and died in 1480. He was a famous student of the even greater Maharil, Rabbi Ya'akov Möllin.
