The horrors of the siege are depicted in the images of fire and a net. The meaning of these is as follows:
The judgment of God is first depicted by fire from on high (i.e, fire sent from God out of heaven). This alludes to the historic judgement over Sodom and Gomorrah (Genesis 19:23–29). It also alludes to more predictions of fiery judgement over other cities (see Amos 1:3–2:5). Here it is significant that the fire descended into the bones of personified Jerusalem.1 The fire’s reach to the very bones stresses the intensely personal way in which the judgment of God touches the innermost part of Jerusalem. (Bones are considered as that part of the body in which pain is most intensely felt.) It is an image of the profound and totally destructive nature of God’s judgement.
As men lay nets to catch birds, so the Lord has laid a net for Jerusalem's feet. This is a commonly used image in the Bible (Job 19:6; Psalm 10:9; Psalm 35:7; Psalm 57:7; Psalm 140:6; Proverbs 29:5; Ezekiel 12:13; Ezekiel 17:20; Ezekiel 19:8; Ezekiel 32:3; Hosea 7:12).2 In this image, Jerusalem has become the object of God’s hunting activities — He has become like an enemy to her. The image is concluded by the notion that escape was impossible; those who attempt escape will only be sent back to the fiery judgment.3
13 “From on high he sent fire; into my bones he made it descend; he spread a net for my feet; he turned me back; he has left me stunned, faint all the day long.