From The Way of the Fathers - Praying with The Early Christians by Mike Aquilina:

Freedom 

See how the Father attracts. He delights in teaching, and not in imposing necessity on men.

- St. Augustine

He who is good is free, even if he is a slave. He who is evil is a slave, even if he is free.

- St Augustine

He who created you without your cooperation does not justify you without your cooperation. He created you without your knowing it; He does not justify you without your wanting it.

 -St Augustine

Christians are forbidden to correct the stumblings of sinners by force... It is necessary to make a man better not by force but by persuasion. We neither have authority granted us by law to restrain sinners, nor, if it were, should we know how to use it, since God gives the crown to those who are kept from evil not by force, but by choice. -St. John Chrysostom

It depends on us whether we wish to be saved. - Anonymous

In all our actions, God considers the intention: whether we act for Him or for some other motive.

- St. Maximus the Confessor

There is nothing to keep you from changing your evil way of life. You are a free man.

-St. Melito of Sardis

Not only in faith, but also in works, God has given man freedom of the will. -St. Irenaeus

Free will is not taken away because it is assisted, but it is assisted in order that it not be taken away.

-St. Augustine