Sefer HaChinuch ספר החינוך

Not to reduce her flesh, covering and time period: That anyone who acquires a Hebrew bondwoman and designates her may not reduce her flesh, her covering and her time period. And the explanation (Ketuvot 47b) of “flesh” is food, of “covering” is like its simple understanding and of “time period” is the way of the world (conjugal rights). And included in this negative commandment are all daughters of Israel (as well), not to reduce from them any thing from these [categories]. [This inclusion] is a fortiori (kal ve’chomer): If he does not reduce for [bondwomen], all the more so for free [women]. And [about] that which it is written (Exodus 21:9), “like the statute of the daughters he shall do for her” — they said in the Mekhilta DeRabbi Yishmael 21:9:2 that it came to learn [from the others], but it ends up to teach, as the [law of the other] daughters are learned from her.

From the laws of this commandment — that which our Rabbis, may their memory be blessed, said (Ketuvot 56a), what is the law of one who stipulates [to marry] his wife “on condition that you do not have [the rights] from me of flesh, covering and time period”; that which they said (Ketuvot 61a), “A woman rises with [the economic standards of a new] husband, but does not descend,” and hence we calculate her food and clothing [allowance] according to his elevation; the matter of the differentiation of time periods, which is according to the strain of the man’s profession, to the point where they, may their memory be blessed, said (Ketuvot 62b) that the time period of a sailor is twice a year, a camel rider once a month and a Torah scholar once a week and it is fitting for him that it be on Shabbat night; and the rest of its details — are [all] elucidated scattered in the Order of Nashim.

And this commandment is practiced regarding a free woman in every place and at all times by males. And one who transgresses it and reduced one of these three from his wife willingly, from the angle of intending to hurt her, has violated this negative commandment (Sefer HaMitzvot, Negative Commandments 262). And it is like he has transgressed the warning of the King. But we do not administer lashes for it, since there is no act [involved] with it.