"The Spirit of the Lord is upon me, because he hath anointed me to preach the gospel to the poor; he hath sent me to heal the brokenhearted, to preach deliverance to the captives, and recovering of sight to the blind, to set at liberty them that are bruised." (Luke 4: 18)
Jesus Christ came to set us free from sin and grant us His righteousness.
The liberty which he proclaimed does not depend on our rule-keeping, our behavior, or even our standing in the world or the amount of money that we have.
In the original Greek, "liberty" is the translation of ἄφεσις, aphesis, which means "release, let go, send away", as in we are released from our sins, which are sent away into the Body of Christ.
Jesus said in the Gospel of John:
"32And ye shall know the truth, and the truth shall make you free." (John 8: 32)
The Gospel of John defines early the key element of Truth:
"14And the Word was made flesh, and dwelt among us, (and we beheld his glory, the glory as of the only begotten of the Father,) full of grace and truth." (John 1: 14)
"17For the law was given by Moses, but grace and truth came by Jesus Christ." (John 1: 17)
In John 1: 17, "grace and truth" are treated as one item, and both are found in Jesus Christ.
Truth is on the side of grace, not on the side of law. The truth sets us free, the truth that in Christ all our sins are forgiven, for grace grants to us by Jesus' death what we can never earn by keeping God's law.
Liberty is based on Grace, and we receive in through Jesus Christ:
"If the Son therefore shall make you free, ye shall be free indeed." (John 8: 36)