Musar zu Wajikra 23:16

But at that very moment Israel declared, ‘We will do’ before ‘We will hear’ (Shemos 24:7) and all of them were shown to be righteous, as it is stated, “You are entirely beautiful, my beloved, and there is no flaw in you” (Shir HaShirim 4:7). And it is also said of them, “Who can find a woman of valor” (Mishlei 31:10) and, “A woman of valor is a crown for her husband” (Mishlei 12:4). Therefore the Zohar (ibid., 96b) refers to the flour offering of Shavuos as a “jealousy offering” (Bamidbar 5:18). It is also called a “new flour offering” (Vayikra 23:16) because Israel was as if created anew the day the Torah was given. Thus they resembled a straying wife who is discovered to be unsullied, of whom it is stated, “She shall be exonerated and seed shall be sown and she shall be pure” (Bamidbar 5:28). And so did Israel become pure after they brought the Shavuos offering.