The freedom Jesus Christ spoke of is a "freedom from sin."
The Pharisees could not perceive that they were enslaved...
Joh 8:32 And ye shall know the truth, and the truth shall make you free.
Joh 8:33 They answered him, We be Abraham's seed, and were never in bondage to any man: how sayest thou, Ye shall be made free?
Jesus clarified their slavery in the context of "committing sin."
Joh 8:34 Jesus answered them, Verily, verily, I say unto you, Whosoever committeth sin is the servant of sin.
Jesus then claimed that it is the Son whom can set them free from committing sin indeed...
Joh 8:35 And the servant abideth not in the house for ever: but the Son abideth ever.
Joh 8:36 If the Son therefore shall make you free, ye shall be free indeed.
We see this reflected in the words of Paul...
Rom 6:16 Know ye not, that to whom ye yield yourselves servants to obey, his servants ye are to whom ye obey; whether of sin unto death, or of obedience unto righteousness?
Paul then states that "freedom from sin" is wrought through "obedience from the heart."
Rom 6:17 But God be thanked, that ye were the servants of sin, but ye have obeyed from the heart that form of doctrine which was delivered you.
Rom 6:18 Being then made free from sin, ye became the servants of righteousness.
This is why Paul taught that the Gospel and the preaching of Jesus Christ was made known to all the nations for obedience of the faith.
Rom 16:25 Now to him that is of power to stablish you according to my gospel, and the preaching of Jesus Christ, according to the revelation of the mystery, which was kept secret since the world began,
Rom 16:26 But now is made manifest, and by the scriptures of the prophets, according to the commandment of the everlasting God, made known to all nations for the obedience of faith:
Jesus is basically inviting all people into union with God through the Spirit of His life. This union is true freedom indeed because all our works become alive through the Spirit, thus we are no longer slaves to sin, nor are we in bondage to the law, for our hearts have been purified and we simply walk by a faith that works by love in the Spirit of life in Jesus Christ.
It is a beautiful thing and it is true freedom.