Discovery BoxLuke 3:9 
Context3:9 Even now the ax is laid at the root of the trees, 1 and every tree that does not produce good fruit will be 2 cut down and thrown into the fire.”
Luke 3:17
Context3:17 His winnowing fork 3 is in his hand to clean out his threshing floor and to gather the wheat into his storehouse, 4 but the chaff he will burn up with inextinguishable fire.” 5
1 sn Even now the ax is laid at the root of the trees. The imagery of an “ax already laid at the root of the trees” is vivid, connoting sudden and catastrophic judgment for the unrepentant and unfruitful. The image of “fire” serves to further heighten the intensity of the judgment referred to. It is John’s way of summoning all people to return to God with all their heart and avoid his unquenchable wrath soon to be poured out. John’s language and imagery is probably ultimately drawn from the OT where Israel is referred to as a fruitless vine (Hos 10:1-2; Jer 2:21-22) and the image of an “ax” is used to indicate God’s judgment (Ps 74:5-6; Jer 46:22).
2 tn Grk “is”; the present tense (ἐκκόπτεται, ekkoptetai) has futuristic force here.
3 sn A winnowing fork is a pitchfork-like tool used to toss threshed grain in the air so that the wind blows away the chaff, leaving the grain to fall to the ground. The note of purging is highlighted by the use of imagery involving sifting though threshed grain for the useful kernels.
4 tn Or “granary,” “barn” (referring to a building used to store a farm’s produce rather than a building for housing livestock).
5 sn The image of fire that cannot be extinguished is from the OT: Job 20:26; Isa 34:8-10; 66:24.
