The word "he" refers to the enemy king and his army. The great size of the army is spoken of as if they were giant storm clouds. AT: "See, great armies like giant clouds are gathering to attack" or "See, great armies are gathering to attack" (See: [[rc://en/ta/man/translate/figs-simile]])
The enemies' chariots are spoken of as if they were like a storm. Storms can be noisy, destructive, and fast-moving. AT: "the roar of their chariots coming is like a fierce storm" (See: [[rc://en/ta/man/translate/figs-simile]])
This can be stated in active form. AT: "for they will devastate us" or "for they will destroy us all" (See: [[rc://en/ta/man/translate/figs-activepassive]])
This is a warning to the people living in Jerusalem to repent. "Cleanse your heart" is a metaphor for removing evil from their lives. AT: "People of Jerusalem, stop being evil" or "People of Jerusalem, stop living wickedly" (See: [[rc://en/ta/man/translate/figs-metaphor]])
This question is used to rebuke the people for always planning how to sin. AT: "Your deepest thoughts are about how to sin!" or "You are always thinking about how to sin!" (See: [[rc://en/ta/man/translate/figs-rquestion]])
# a voice is bringing news from Dan
Here "a voice" represents a messenger. AT: "a messenger comes and tells about what is happening in Dan" (See: [[rc://en/ta/man/translate/figs-synecdoche]])
# Dan
This probably refers to the region of Dan, which was west of Jerusalem.
# the coming disaster is heard from the mountains of Ephraim
This can be stated in active form. AT: "people hear about the disaster that is coming from Ephraim" (See: [[rc://en/ta/man/translate/figs-activepassive]])