NOTES for Luk 3:17
The coming of the Messiah in gospel times was associated by most of those who awaited Him with the day of God's judgment. This is not surprising, for the Messiah was to establish His Kingdom on earth, and not everyone could enter that Kingdom, only the righteous. Therefore the day of the Messiah's coming and the arrival of the messianic Kingdom had by definition to be also the day of Judgment. True, this Judgment was understood differently, so that in popular religiosity one can find many images describing it.
One of these images John uses in his preaching. At its foundation lies the picture of humanity being separated, and this separation is symbolically described as the winnowing of wheat during harvest. This is an image to which the Savior Himself more than once turned during His earthly ministry, and it evidently proved very apt for describing what will happen on the day of the Kingdom's triumph and the final Judgment. The issue is the separation between the righteous and sinners. But here it is not simply separation; it is rather a kind of verification, a test for correspondence.
Grain to one side, chaff to the other: this is clear. But grain differs qualitatively from chaff; they even have different weight, and the difference in weight is because the grain is filled, while chaff is empty, only husk, an empty shell. Here lies the main difference between those entering the Kingdom and those remaining outside. The whole question is with what a person comes to the threshold of the Kingdom. Whether he is full or empty. And this in turn depends on the path the person has traveled. Righteousness is above all connected with that presence of God without which it simply cannot exist. This presence fills the person. It makes him grain. But if there is nothing of the kind, if a person goes through life seeking no presence of God or not thinking about God at all, then there will be nothing to fill him. At the end of the path, at the threshold of the Kingdom, he will be empty. It is not God who judges and drives a person away from this threshold. One could say that the person judges himself. Or more exactly, the path he has traveled becomes judgment for him. Traveled either with God or without Him.