Verse 17: So she gleaned in the field until even, and beat out that she had gleaned: and it was about an ephah of barley.
[About the measure of an ephah] An ephah is a sort of measure of dry goods, and contains three sata (Vatablus, Drusius). Concerning which see Exodus 16:36 (Piscator).
[Of barley] Hebrew: of barleys, that is, of barley-grains (Piscator).
[כְּאֵיפָ֥ה שְׂעֹרִֽים׃] In the place of אֵיפַת, the absolute state in the place of the construct; as elsewhere. Thus, in Deuteronomy 16:21, אֲשֵׁרָ֖ה כָּל־עֵ֑ץ, a grove of every tree, in the place of אֲשֵׁרַת; which Kimchi expounds by ellipsis, that is to say, אֲשֵׁרָה אֲשֵׁרַת, a grove, a grove, I say, of every tree (Bochart’s Sacred Catalogue of Animals 2:2:17:248).
An ephah is thought to contain about a bushel. See Exodus 16:36; Leviticus 5:11.
Verse 18: And she took it up, and went into the city: and her mother in law saw what she had gleaned: and she brought forth, and gave to her (Ruth 2:14) that she had reserved after she was sufficed.
[She gave to her of the rest of the food, etc., אֲשֶׁר־הוֹתִ֖רָה מִשָּׂבְעָֽהּ׃] What she had left of her fullness (Pagnine, Montanus, Piscator); what of her repast she had left, having been satisfied (Vatablus); of which, or, of that whereby, she had been satisfied (Piscator, Junius and Tremellius). The remainders of the food, wherewith she had been satisfied, she gave to her mother-in-law: or, She brought forth the Ephah of barley, and at the same time she gave to her the food that had been left over (Drusius). She gave to her of the presents for guests to take away with them (Grotius).
That she had reserved after she was sufficed: Or, that which she had left of her fulness, or after she was satisfied. She did eat as much as she desired of what she had gleaned, and her mother, as I suppose, with her, and the residue she gave to her mother to lay up for future use.
 Hebrew: וַתְּלַקֵּ֥ט בַּשָּׂדֶ֖ה עַד־הָעָ֑רֶב וַתַּחְבֹּט֙ אֵ֣ת אֲשֶׁר־לִקֵּ֔טָה וַיְהִ֖י כְּאֵיפָ֥ה שְׂעֹרִֽים׃
 A satum contains about three dry gallons.
 Hebrew: שְׂעֹרִים.
 An bushel is approximately eight dry gallons.
 Hebrew: וַתִּשָּׂא֙ וַתָּב֣וֹא הָעִ֔יר וַתֵּ֥רֶא חֲמוֹתָ֖הּ אֵ֣ת אֲשֶׁר־לִקֵּ֑טָה וַתּוֹצֵא֙ וַתִּתֶּן־לָ֔הּ אֵ֥ת אֲשֶׁר־הוֹתִ֖רָה מִשָּׂבְעָֽהּ׃