Sforno on Deuteronomy 32:18/ספורנו על דברים ל״ב:י״ח

1צור ילדך תשי, even you, Yeshurun, the one blessed with erudition, once you turned your attention to the physical enjoyments of life on earth, undermined, weakened your wisdom and your knowledge about the greatness of G’d and His Torah.

2ותשכח א-ל מחוללך, Who had treated you so well. Compare Isaiah 51, 12-13 אנכי הוא מנחמכם...ותשכח ה' עושך נוטה שמים וארץ, “I, I am He Who comforts you!…You have forgotten the Lord your Maker, Who stretched the skies and made firm the earth.”