Isaiah 54:6
For the LORD hath called thee as a woman forsaken and grieved in spirit, and a wife of youth, when thou wast refused, saith thy God. For the LORD hath called thee as a woman forsaken and grieved in spirit, and a wife of youth, when thou wast refused, saith thy God.
The Lord calls out to one who feels forsaken and grieved in spirit, picturing her as a wife of youth who is refused after the closeness of her youth. That forsaken and grieved wife is His people, whom He as Maker and Husband calls back, and the picture fits the church when she leaves her first love and joins herself to the world. The rejected and grieving one is reassured that He has called her and has not forgotten her sorrows, that her grief does not mean abandonment, and that He remains her God and will gather her with great mercy after a brief withdrawal. The verses around it assure that God restores and comforts the afflicted, bringing the promise that Jesus will take the burden and give rest.
It belongs to a prophecy about the work of Christ and stands as a help and blessing to His people. Together with Isaiah 55 and Isaiah 58 it shows a precious and extended work for God's people in the last days of earth's history, part of lifting up Christ before the world. In that work believers do not only sit in church Sabbath after Sabbath listening to the same truths but visit friends and neighbors in their families, create an interest in present truth, plant the Word of God in hearts, and deal out the bread of life to hungering souls while working intelligently together with God for salvation. Mercy is sought by doing the very work God has laid out to do in this world, for the blessing of God does not rest on those who do nothing but on those who take hold of the Word of God and the encouragement He has given and wrench souls from Satan's grasp.