The Gemara in Masechet Pesachim establishes the requirement of Heseba – to lean at various points during the Seder (such as when eating Masa and drinking the four cups of wine) as an expression of our freedom. The Sages went so far as to make Heseba a prerequisite for fulfilling the various Misvot; if one did not lean while eating Masa, for example, he has not fulfilled the Misva of Masa and must eat Masa again.
There is, however, one opinion among the Rishonim, the view of the Re’aveya (Rabbi Eliezer Ben Yoel Ha’levi, Germany, 1140-1220), that this obligation does not apply nowadays. Since people don’t normally eat in this fashion, and we instead eat in an upright position, leaning no longer expresses freedom, and thus it is not required at the Seder.
Although the Re’aveya’s position has not been accepted as normative Halacha, it nevertheless behooves us to understand its rationale. There is a fundamental Halachic principle that if the Rabbis enacted a certain law, it remains binding even if its reason is no longer applicable, unless a group of Rabbis of equal stature formally revoke the provision. How, then, could the Re’aeveya claim that the obligation of Heseba no longer applies nowadays?
Hacham Ovadia Yosef addresses this question in his Hazon Ovadia – Responsa (Siman 14, p. 217), and offers several different approaches to explain the Re’aveya’s ruling. One approach is that already when the law of Heseba was enacted, it took into account conventional practice. Thus, for example, the She’iltot writes that women are not required to lean at the Seder because it was not customary for women to eat in a leaning position. This clearly shows that already from the outset, the requirement of Heseba was subject to conventional practice and protocol. Hence, the Re’aveya did not introduce any new concept; he merely applied this "built-in" condition to all people once it became customary for all people, men and women alike, to eat in an upright position.
Secondly, Hacham Ovadia writes, although a Halacha enacted by Hazal remains binding even once its reason is no longer applicable, in this instance, the Halacha’s objective is actually undermined by abiding by the law. As mentioned, Hazal required that we lean at the Seder as an expression of our freedom. But now that it is no longer common to eat in this fashion, a person who leans while eating does not appear free; to the contrary, he appears ill. The Re’aveya thus felt that since the purpose of the Halacha would actually be undermined by leaning, the Halacha no longer applies and there is no longer any requirement to lean.
Hacham Ovadia further suggests that the requirement of Heseba may not have been established by a formal enactment of the Sanhedrin, and thus it is not binding once the underlying reason is no longer applicable.
As mentioned, Halacha does not accept the view of the Re’aveya, and requires Heseba at the Seder for both men and women. The Aruch Ha’shulhan (Rav Yechiel Michel Epstein of Nevarduk, 1829-1908) explains that to the contrary, the fact that we do not normally eat in a leaning position nowadays is actually a compelling reason to lean at the Seder. We do many things at the Seder to pique the children’s interest so they will ask questions and get involved, and Heseba fills this role. Indeed, the fourth of the Ma Nishtana questions is why we eat on this night in a leaning position. This question does not appear in the original text of the Ma Nishtana mentioned in the Mishna, because in the times of the Mishna leaning was a normal manner of eating and thus did not strike children as unusual. In our times, however, leaning is an effective way of conveying to our children that the night of Pesah is special, thus arousing their interest and curiosity. Hence, despite the explanations given in defense of the Re’aveya’s ruling, in practice, we require Heseba even nowadays.
Summary: The requirement of Heseba – to lean at various points during the Seder – applies even nowadays, when this is not a conventional way of eating.
