What is the Pasuk coming to teach us? What is the significance of the comparison to a father chastising his son?
Ramban: Like a father places on his son the yoke of Musar (teaches him ethics) for his own good, 1 so too, was Hashem chastising Yisrael, with the afflictions of the desert and the test of the Manna, so that they would ultimately appreciate the goodness of Eretz Yisrael and its fruit. 2
Seforno: Just like a father who chastises his son, Hashem chastises Yisrael (not with the intention of harming them, but) in order to prompt them to attain the level of perfection that He expects of them.