Isaiah tells Israel to prepare for the coming of Yahweh by leveling mountains and raising valleys (40:3-5), and when Yahweh comes the mountains melt away (Psalm 97:5; Micah 1:4).
But the angel of Yahweh tells Zechariah that the mountains will give way to Zerubabbel (Zechariah 4:7), a true son of David and son of Yahweh. Jesus makes the same promise to His disciples; they are all Zerubbabels, who can say to this mountain “Cast yourself into the sea,” and it will happen (Matthew 21:21).
This is the power of those who walk by the Spirit (Zechariah 4:6).
