Hear ye now what the LORD saith; Arise, contend thou before the mountains, and let the hills hear thy Hear ye now what the LORD saith; Arise, contend thou before the mountains, and let the hills hear thy voice.
Here begins the third division. After the glorious promises of the coming Messiah (Micah 5:1-15), he passes to the Lord's wonderful pleading with His people for their ungrateful return for all His continued loving-kindness.
Hear ye now what the Lord saith; Arise, contend thou - Israel is called by Yahweh to plead with Him in controversy. Micah 5:11-13 ("I will cut off ... all thy strong holds ... witchcrafts ... soothsayers ... graven images ... standing images ... groves") suggested the transition from those happy times described in Micah 4:1-13 and Micah 5:1-15 to the prophet's own degenerate times and people.
Before the mountains - in their presence; personified as if witnesses (cf. Micah 1:2; Deuteronomy 32:1; Isaiah 50:2). Not as margin, 'with;' as God's controversy is with Israel, not with them.