Guide for the Perplexed, by Moses Maimonides, Friedländer tr. [1904], at sacred-texts.com
SINCE the verb "to say" has been figuratively used to express the will of the Creator, and the phrase "And he said has repeatedly been employed in the account of all the things created in the six days of the beginning," the expression "to rest" has likewise been figuratively applied to God in reference to the Sabbath-day, on which there was no creation; it is therefore said, "And he rested (va-yishbot) on the seventh day" (Gen. ii. 2). For "to leave off speaking" is, in Hebrew, likewise expressed by the same verb, as, e.g., "So these three men ceased (va-yishbetu) to answer Job" (Job xxxii. 1) also by nuaḥ, as, in "They spake to Nabal according to all those words in the name of David, and ceased (va-yanuḥu)" (1 Sam. xxv. 9). In my opinion, (va-yanuḥu) means "they ceased to speak," and waited for the answer; for no allusion to exertion whatever having previously been mentioned, the words, "and they rested," in its primary signification, would have been entirely out of place in that narrative, even if the young men who spoke had really used some exertion. The author relates that having delivered that whole speech, which, as you find, consisted of gentle expressions, they were silent, that is to say, they did not add any word or act by which the reply of Nabal could be justified: it being the object of the entire passage to represent Nabal's conduct as extremely reprehensible. In that sense [viz., "to cease," or "to leave off"] the verb nuaḥ is used in the phrase "And he left off (va-yanaḥ) on the seventh day."
Our Sages, and some of the Commentators, took, however, nuaḥ in its primary sense "to rest," but as a transitive form (hiphil), explaining the phrase thus: "and he gave rest to the world on the seventh day," i.e., no further act of creation took place on that day.
It is possible that the word va-yanaḥ is derived either from yanaḥ, a verb of the class pe-yod, or naḥah, a verb of the class lamed-he, and has this meaning: "he established" or "he governed" the Universe in accordance with the properties it possessed on the seventh day"; that is to say, while on each of the six days events took place contrary to the natural laws now in operation throughout the Universe, on the seventh day the Universe was merely upheld and left in the condition in which it continues to exist. Our explanation is not impaired by the fact that the form of the word deviates from the rules of verbs of these two classes: for there are frequent exceptions to the rules of conjugations, and especially of the weak verbs: and any interpretation which removes such a source of error must not be abandoned because of certain grammatical rules. We know that we are ignorant of the sacred language, and that grammatical rules only apply to the majority of cases.--The same root is also found as a verb ‘ayin-vav in the sense "to place" and
[paragraph continues] "to set," as e.g., "and it shall be established and she shall be placed (ve-hunniḥah) there upon her own base" (Zech. v. 11), and "she suffered neither the birds of the air to settle (la-nuaḥ) on them" (2 Sam. xxi. 10). According to my opinion, the verb has the same signification in Hab. in. 16, "that I might remain firm (anuaḥ) in the day of trouble."
The word (va-yinnafash) is a verb derived from nefesh, the homonymity of which we have already explained (chap. xli.), namely, that it has the signification of intention or will: (va-yinnafash) accordingly means: "that which he desired was accomplished, and what he wished had come into existence."