The Lord's people are to prove it is in deep troubles the the Lord appears and gives them hope.
Sin was dealt with very thoroughly in the valley of Achor, removing the curse and allowing the Lord to bless and go with the children of Israel again.
Our Lord dealt fully with our sin at Calvary,enduring the wrath of God and making full atonement.
1/ What went before the valley of Achor
2/ The Valley of Achor
3/ How the valley of achor is given as a door of hope