Leviticus - Chapter 25

In this chapter we are told of the Year of Jubilee - the fiftieth year:

Consecrate the fiftieth year and proclaim liberty throughout the land to all its inhabitants.  It shall be a jubilee for you.  

This is a year when slaves will be set free.  It was the year of the Lord's favour.

At the very start of his ministry, Jesus announces his purpose, making a clear reference to the Jubilee.  This is recorded in Luke 4:

He went into the synagogue on the Sabbath day, and stood up to read.  And He was handed the book of the prophet Isaiah. And when He had opened the book, He found the place where it was written:  “The Spirit of the Lord is upon Me, because He has anointed Me to preach the gospel to the poor; He has sent Me to heal the brokenhearted, to proclaim liberty to the captives and recovery of sight to the blind, to set at liberty those who are oppressed; to proclaim the acceptable year of the Lord.” Then He closed the book, and gave it back to the attendant and sat down. And the eyes of all who were in the synagogue were fixed on Him. And He began to say to them, “Today this Scripture is fulfilled in your hearing.”