The wrath of God came upon them, and slew the strongest of them, and struck down the chosen men of Israel.
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Augustine of Hippo
AD 430
16. But as to unbelievers, being a crooked and embittering generation, as it were, while the morsel was yet in their mouths, "the anger of God went up upon them, and it slew among the most of them" (ver. 31): that is, the most of them, or as some copies have it, "the fat ones of them," which however in the Greek copies which we had, we did not find. But if this be the truer reading, what else must be understood by "the fat ones of them," than men mighty in pride, concerning whom is said, "their iniquity shall come forth as if out of fat"? "And the elect of Israel He lettered." Even there there were elect, with whose faith the generation crooked and embittering was not mixed. But they were fettered, so that they might in no sort profit them for whom they desired that they might provide from a fatherly affection. For what is conferred by human mercy, on those with whom God is angry? Or rather hath He willed it to be understood, how that even the elect were fettered at the same time with ...
Israel. St. Jerome applies this to those who receive unworthily, particularly if they be priests, 1 Corinthians xi. 29. (Calmet)
God selected the most guilty (Berthier) having allowed them to feast for a whole month. (Worthington)
Then he brought down by death, or "hindered "as it were, "by shackles "(Septuagint) the most valiant. (Haydock)