The sugya is Kiddushin 33b–35a. Mitzvat ‘aseh she-ha-zeman geramah is literally: ‘A positive precept that is caused by time’, i.e. that depends for its performance on a given time and is not a precept that can be carried out at any time. The sugya is appended to the Mishnah (Kiddushin 1:7): ‘And every positive precept dependent on time men are obliged to fulfil but women are exempt. And every positive precept not dependent on time both men and women are obliged to fulfil. And every negative precept, whether dependent on time or not dependent on time, both men and women are obliged to fulfil.’

The sugya opens with a Baraita: ‘Which are positive precepts dependent on time: sukkah (Leviticus 23: 42, only to be carried out on Tabernacles); lulav (‘palm branch, Leviticus 23: 40, only on Tabernacles); shofar (ram's horn’, Leviticus 23: 24; Numbers 29: 1, only on the New Year Festival); tzitzit (‘fringes’, Numbers 16: 38, only during the day, not at night); and tefillin (Deuteronomy 6: 8, only during the days and not the nights of the week and not on Sabbath and Festivals). And which are positive precepts not dependent on time: mezuzah (Deuteronomy 6:9); ma'akeh (‘battlement’, Deuteronomy 22: 8); returning lost property (Exodus 23: 4; Deuteronomy 22: 1–3); and sending away the mother-bird (Deuteronomy 22: 6–7).’

The Talmud objects: but is this a general rule? There are: eating unleavened bread on Passover (Exodus 12: 18, obligatory for women, too, just as they are obliged to abstain from eating leaven); rejoicing on the Festivals (Deuteronomy 16: 14); and assembly (on the Festival of Tabernacles in the seventh year, Deuteronomy 31: 12).