Isaiah describes the people of God in the following way in ch. 21: ‘O my threshed and winnowed one, what I have heard from the Lord of hosts, the God of Israel, I announce to you’ (21:10).
This same imagery of the people of God as wheat mixed with chaff is carried over into the New Testament. For example, Luke records that John the Baptist describes Christ thus: ‘His winnowing fork is in his hand, to clear his threshing floor and to gather the wheat into his barn, but the chaff he will burn with unquenchable fire’ (3:17).
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