זְכֹר֙ אַל־תִּשְׁכַּ֔ח אֵ֧ת אֲשֶׁר־הִקְצַ֛פְתָּ אֶת־יְהוָ֥ה אֱלֹהֶ֖יךָ בַּמִּדְבָּ֑ר לְמִן־הַיּ֞וֹם אֲשֶׁר־יָצָ֣אתָ ׀ מֵאֶ֣רֶץ מִצְרַ֗יִם עַד־בֹּֽאֲכֶם֙ עַד־הַמָּק֣וֹם הַזֶּ֔ה מַמְרִ֥ים הֱיִיתֶ֖ם עִם־יְהוָֽה׃
געדענק, זאָלסט ניט פֿאַרגעסן, װי דו האָסט דערצערנט ה׳ דײַן גאָט אין דער מדבר; פֿון דעם טאָג אָן װאָס דו ביסט אַרױסגעגאַנגען פֿון לאַנד מִצרַיִם, ביז אײַער קומען צו דעם דאָזיקן אָרט, זײַט איר װידערשפּעניקער געװען אַקעגן גאָט.
Chizkuni
אשר הקצפת במדבר, “how you made the Lord your G-d angry in the desert;” this occurred already immediately after the people had broken camp after over 11 months at Mount Sinai. (Ibn Ezra)
Sforno
זכור אל תשכח, Moses adds proof to his characterising the Jewish people as being stiff-necked by reminding them of how many times during his stewardship of the nation they had angered G’d, so that it reminds one of a dog which returns to his own excrement finding it attractive. This happened again and again although each time they had been subjected to disciplining by G’d, and they learned more about His greatness on each occasion.