Can I Make Up My Own Gezeirah Shavah?

On Rosh HaShana, Sarah, Rachel, & Hannah were revisited. From where do we derive this? Rabbi Elazar said: This is derived by means of a verbal analogy between one instance of the term revisiting [pekida] and another instance of the term revisiting, and by means of a verbal analogy between one instance of the term remembering [zekhira] and another instance of the word remembering. It is written about Rachel: “And God remembered Rachel”, and it is written about Hannah: “And the Lord remembered her”. And the meaning of these instances of the term remembering is derived from another instance of the term remembering, with regard to Rosh HaShana, as it is written: “A solemn rest, memorial proclaimed with the blast of a shofar”. And the meaning of one instance of the term revisiting is derived from another instance of the term revisiting. It is written about Hannah: “And the Lord revisited Hannah”, and it is written about Sarah: “And the Lord revisited Sarah”.

In accordance with what Rav Pappa said: “the twentieth year” may be inferred from another instance of the expression “the twentieth year” by way of a verbal analogy, here too, the meaning of one instance of the expression “the fortieth year” may be inferred from another instance of the expression “the fortieth year” by way of a verbal analogy: Just as here, with regard to Aaron’s death, the count is from the exodus from Egypt, so too, here, with regard to Moses’ oration the count is from the exodus from Egypt.

§ The first of Tishrei is also the New Year for calculating Sabbatical Years. The Gemara asks: From where do we derive this? As it is written: “But in the seventh year shall be a Shabbat of solemn rest for the land” and we learn by way of a verbal analogy between one instance of the word “year” and another instance of the word “year” that the year begins for this purpose from Tishrei, as it is written: “From the beginning of the year”. But let us learn by way of a verbal analogy between one instance of the word “year” and another instance of the word “year” and conclude that for this purpose the year begins from Nisan, as it is written: “It shall be the first month of the year to you” The Sages derive the meaning of the word “year” that appears in the verse about the Sabbatical Year, where months are not mentioned with it, from the word “year” that appears in the verse in Deuteronomy above, where months are also not mentioned with it. And they do not derive the meaning of the word “year” where months are not mentioned with it from the word “year” that appears in the verse where months are mentioned with it.

But since Hillel learned this verbal analogy from his teachers, why do I need an a fortiori inference? Rather, he said it for them: Granted, you did not learn the verbal analogy, because you acted according to the principle that one may not expound a verbal analogy on one’s own. But an a fortiori inference, which one can derive on one’s own, you should have derived and you would then have known. They said to him: It is a faulty a fortiori.

Rav Aḥa, son of Rava, teaches in the name of Rabbi Elazar a lenient version: With regard to any verbal analogy that is not free at all, one can derive halakhot from it, but one can also refute it logically. If the verbal analogy is free on one side, according to Rabbi Yishmael one can derive halakhot from it, and one cannot refute it. According to the Rabbis, one can derive halakhot from it, but one can also refute it. If the verbal analogy is free on both sides, everyone agrees that one can derive halakhot from it and one cannot refute it. If the verbal analogy is free on both sides, everyone agrees that one can derive halakhot from it and one cannot refute it.

Granted, the statement of Rabbi Akiva of the mishna is reasonable, as a verbal analogy does not come and divert the verse from its plain meaning entirely. However, according to Rabbi Akiva of the baraita, does a verbal analogy come and divert the verse from its plain meaning entirely?

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The Gemara analyzes the baraita. This tanna initially derives his halakha from juxtaposition, based on the phrase: “Of the seventh month,” which teaches that every sounding of the shofar in the seventh month must be alike. And now he derives this halakha that one sounds three tekia-terua-tekia sets by verbal analogy from the recurrence of the term “seventh.” How can the tanna change his method of derivation in the very same baraita? The Gemara explains that this is what the tanna is saying: If there were no verbal analogy, I would have derived this halakha by juxtaposition. Now that it is derived through a verbal analogy, the juxtaposition is not necessary.

Rather, this is what Rabbi Meir was saying to the Rabbis: Learn this halakha from the following verbal analogy: It is written here: “Your shoots [shelaḥayikh] are an orchard of pomegranates”, and it is written there: “and sends [veshole’aḥ] waters upon the fields”. And the Rabbis disagree with Rabbi Meir, as they do not have a tradition that this is an accepted verbal analogy, and there is a principle that although a person may derive an a fortiori inference on his own, i.e., even though he was not taught that particular logical argument by his teachers, a person may not derive a verbal analogy on his own, but only if he received it by tradition.