בַּבֹּ֤קֶר תֹּאמַר֙ מִֽי־יִתֵּ֣ן עֶ֔רֶב וּבָעֶ֥רֶב תֹּאמַ֖ר מִֽי־יִתֵּ֣ן בֹּ֑קֶר מִפַּ֤חַד לְבָֽבְךָ֙ אֲשֶׁ֣ר תִּפְחָ֔ד וּמִמַּרְאֵ֥ה עֵינֶ֖יךָ אֲשֶׁ֥ר תִּרְאֶֽה׃
Pela manhã dirás: Ah! quem me dera ver a tarde; E à tarde dirás: Ah! quem me dera ver a manhã! pelo pasmo que terás em teu coração, e pelo que verás com os teus olhos.
Rashi on Deuteronomy
בבקר תאמר מי יתן ערב IN THE MORNING THOU SHALT SAY, WOULD IT WERE EVEN! — i.e. would that it were again yesterday evening,
Rashbam on Deuteronomy
מי יתן ערב, according to the plain meaning this refers to the following evening; this is the way the sick people react to their condition, assuming that they will start to get better by then.
Siftei Chakhamim
That it were last evening. Rashi is answering the question: Logic would dictate the opposite [of what the verse says], because it says in Bava Basra (16b), “When the sun is high, illness is relieved,” which indicates that illness is worse in the evening than in the morning! Regarding this he explains, “That it were last evening.”