You will go out in joy
    and be led forth in peace;
the mountains and hills
    will burst into song before you,
and all the trees of the field
    will clap their hands.
13 Instead of the thornbush will grow the juniper,
    and instead of briers the myrtle will grow.
This will be for the Lord’s renown,
    for an everlasting sign,
    that will endure forever.”

God’s Word is His work. What He says will happen. His Word will not return to Him ”empty” (11). His people will return from exile to their homeland. They will go joyfully, peacefully, musically. They will experience miraculous transformation. It will all be for God’s glory. Why? Because He wills and decrees it.

”They shall go out of their captivity, and be led forth towards their own land again. God will go before them as surely, though not as sensibly, as before their fathers in the pillar of cloud and fire. They shall go out, not with trembling, but with triumph, not with any regret to part with Babylon, or any fear of being fetched back, but with joy and peace. Their journey home over the mountains shall be pleasant, and they shall have the good-will and good wishes of all the countries they pass through. The hills and their inhabitants shall, as in a transport of joy, break forth into singing; and, if the people should altogether hold their peace, even the trees of the field would attend them with their applauses and acclamations. And, when they come to their own land, it shall be ready to bid them welcome; for, whereas they expected to find it all overgrown with briers and thorns, it shall be set with fir-trees and myrtle-trees: for, though it lay desolate, yet it enjoyed its sabbaths (Lev 26 34), which, when they were over, like the land after the sabbatical year, it was the better for. And this shall redound much to the honour of God and be to him for a name.” Matthew Henry.