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

1כי מגפן סדום גפנם, the reason that in this matter they do not display their customary insights is that they boast about their secure and unthreatened existence, concerning themselves exclusively with physical gratifications just as had the people of Sodom. In order to attain their maximum gratification they completely eschewed all manner of caring for the less fortunate, as testified to by Ezekiel 16,49 when the prophet said הנה זה היה עוון סדום אחותך, גאון שבעת לחם ושלות השקט היה לה ולבנותיה ויד עני ואביון לא החזיקה. “only this was the sin of your sister Sodom; arrogance! She and her daughters had plenty of bread and untroubled tranquility. Yet she did not support the poor and the needy. “

2ענבימו ענבי רוש, from this vine there sprouted forth for them grapes which are poison. This is a simile for the evil deeds committed by the Jewish people which backfired. The sins singled out are those of a social rather than a theological nature, as pointed out by Ezekiel.

3אשכלות מרורות למו, a bitter growth in their clusters; developing of erroneous philosophies, primarily justifying one’s conduct, rationalising it, is a natural corollary of such attitudes as self-centredness. First and foremost, they convince themselves that G’d does not ”see,” i.e. does not care, [that there is no personal G’d. They totally misinterpret G’d’s patience with the sinner. Ed.]