Church Fathers on Libertarian Free Will

Clement of Rome: (Knew Peter and Paul personally. He was the third or fourth bishop of Rome. Tradition has identified him with the Clement who is mentioned in Philippians 4:3) "For no other reason does God punish the sinner either in the present or future world, except because He knows that the sinner was able to conquer but neglected to gain the victory." Recognitions of Clement of Rome. 111. 23, V. 8, IX. 30. 

Clement of Alexandria: (153-217 AD) "Neither praise nor condemnation, neither rewards nor punishments, are right if the soul does not have the power of choice and avoidance, if evil is involuntary." Miscellanies bk. 1, chap. 17 

To these prophecy says, If you be willing and hear me, you shall eat the good things of the land; Isaiah 1:19 proving that choice or refusal depends on ourselves. The Stromata (Clement of Alexandria) 1.18 (link)

Epiphanius: (310-403) ‘if ye be willing and obedient’; “whence, it is plainly manifest and indubitable, that God had granted to man free-will, so that it is in his power to do the good, or choose the evil. For if it be predestined that one man be good and another man evil, then the first is not deserving of praise or the other to be blamed. Against Heresies 16 Isaiah

Justin: (100-165) Unless humans have the power of avoiding evil and choosing good by free choice, they are not accountable for their actions-whatever they may be... For neither would a man be worthy of reward or praise if he did not of himself choose the good, but was merely created for that end. Likewise, if a man were evil, he would not deserve punishment, since he was not evil of himself, being unable to do anything else than what he was made for." (First Apology chap. 43) 

Tertullian: (207 AD) I find, then, that man was constituted free by God. He was master of his own will and power….Man is free, with a will either for obedience or resistance.(Against Marcon.  Book II, Chapter 5)  

Tertullian: (207 AD) because, if he were wanting in this prerogative of self-mastery, so as to perform even good by necessity and not will, he would, in the helplessness of his servitude, become subject to the usurpation of evil, a slave as much to evil as to good. Entire freedom of will, therefore, was conferred upon him in both tendencies; so that, as master of himself, he might constantly encounter good by spontaneous observance of it, and evil by its spontaneous avoidance; because, were man even otherwise circumstanced, it was yet his bounden duty, in the judgment of God, to do justice according to the motions of his will regarded, of course, as free. But the reward neither of good nor of evil could be paid to the man who should be found to have been either good or evil through necessity and not choice. (Against Marcion, Bk. II, ch. vi) 

Tertullian: (207 AD) "God put the question [to Adam - "where art thou"] with an appearance of uncertainty, in order that even here He might prove man to be the subject of a free will in the alternative of either a denial or a confession, and give to him the opportunity of freely acknowledging his transgression, and, so far, of lightening it. In like manner He inquires of Cain where his brother was, just as if He had not yet heard the blood of Abel crying from the ground, in order that he too might have the opportunity from the same power of the will of spontaneously denying, and to this degree aggravating, his crime; and that thus there might be supplied to us examples of confessing sins rather than of denying them: so that even then was initiated the evangelic doctrine, “By thy words thou shall be justified, and by thy words thou shalt be condemned.” (Against Marcion, Bk. II, xxv) 

Hippolytus: (225 AD) For if man did not possess the power to will and not to will, why should a law be established? …And that by Himself in person He might prove that God made nothing evil, and that man possesses the capacity of self-determination, inasmuch as he is able to will and not to will, and is endued with power to do both. Against all Heresies Book 10, Chapter 29 (link)

Eusebius of Caesarea: (263-339) For the Creator of all implanted in every soul this natural law as a helper and defender in its actions; and while by His law He showed it the right way, by the self-determined freedom bestowed on it He declared the choice of the better course to be deserving of praise and approbation, and of greater honours and rewards for its good deeds, because it performed them not under compulsion but by its own independent decision, though it had the power of choosing the opposite: so that, on the other hand, that soul which chose the worst acts was deserving of blame and punishment, as having 'proprio motu' transgressed the law of nature, and given birth to a source and fount of wickedness, and used itself basely not from any external necessity but of free determination and judgement. 'The chooser then is answerable, God is not to blame.'  For God made neither nature nor yet the substance of the soul evil: since a good Being may not create anything but what is good. Everything, then, that is according to nature is good: and every rational soul possesses by nature the good gift of free-will, which has been given for choosing what is good.  But when it acts wickedly, it is not nature that should be blamed: since evil comes to it not by nature but against nature, being a matter of choice but not an effect of nature. For when one who had power to choose the good, instead of choosing this, voluntarily rejected the better part and claimed the worse, what room for excuse could be left to him after becoming the cause of his own disease, and disregarding the innate law which was, as it were, his preserver and healer?  Praeparatio Evangelica.  Book 6, Chapter 6 (link)

ATHENAGORAS: (177 AD) "Just as with men, who have freedom of choice as to both virtue and vice, so it is among the angels...Some free agents, you will observe, such as they were created by God, continued in those things for which God had made and over which he had ordained them; but some outraged both the constitution of their nature and the government entrusted to them." - A Plea for the Christians 24. 

Novatian:  (200-258) So that he might receive as a consequence both worthy rewards and a deserved punishment, having in his own power that which he might choose to do, by the tendency of his mind in either direction: whence, therefore, by envy, mortality comes back upon him; seeing that, although he might escape it by obedience, he rushes into it by hurrying to be God under the influence of perverse counsel." (Trinity, ch. I) 

Cyprian: (250 AD) The liberty of believing or not believing is placed in free choice. In Deuteronomy, it says, ‘Look! I have set before your face life and death, good and evil. Choose for yourself life, that you may live.’”(Three Books of Testimonies against the Jews.  Book III, Chapter 52 (link) )

Methodius: (290 AD) Man was made with a free will…on account of his capacity of obeying or disobeying God. For this was the meaning of the gift of free will.(On Free Will (link) )

Irenaeus: (c. 175) God therefore has given that which is good, as the apostle tells us in this Epistle, and they who work it shall receive glory and honor, because they have done that which is good when they had it in their power not to do it; but those who do it not shall receive the just judgment of God, because they did not work good when they had it in their power so to do. "But if some had been made by nature bad, and others good, these latter would not be deserving of praise for being good, for such were they created; nor would the former be reprehensible, for thus they were made [originally]. But since all men are of the same nature, able both to hold fast and to do what is good; and, on the other hand, having also the power to cast it from them and not to do it, — (Against Heresies, Bk. IV, 37) 

Archelaus: (320) "This account also indicates that rational creatures have been entrusted with free-will, in virtue of which they also admit of conversions." ... "For all the creatures that God made, He made very good; and He gave to every individual the sense of free-will, in accordance with which standard He also instituted the law of judgment. To sin is ours, and that we sin not is God’s gift, as our will is constituted to choose either to sin or not to sin. ... The judges said: He has given demonstration enough of the origin of the devil. And as both sides admit that there will be a judgment, it is necessarily involved in that admission that every individual is shown to have free-will; and since this is brought clearly out, there can be no doubt that every individual, in the exercise of his own proper power of will, may shape his course in whatever direction he pleases." (The Acts of the Disputation With Manes 32, 33 ) 

Basil the Great: (329-379) Why in short was it receptive to evil? Because it was endowed with free will, which is expecially appropriate for a nature endowed with reason. So the soul is freed of all constraints, and obtains from the Creator a life at its own discretion; and because it was made in God’s image, it understood the good and knows its joys, and has the possibility and power of maintaining its natural life by continuing to gaze on the good and to enjoy the life of the spirit. But it has also the possibility on occasion of abandoning the good. -  God is not the author of Evil (Homily 9)