The most direct starting point is the Torah's framing of bechirah itself: Devarim 30:15-20 sets life and death, good and evil before the person and commands choosing life, and Yehoshua 24:15 similarly calls the people to choose whom to serve, establishing that free choice between good and evil is the baseline condition of the human being.
Chazal personify the yetzer hara as an active force working to subvert that choice: Berakhot 61a describes it as a fly or a kernel of wheat lodged at the heart's entrance advising toward evil, while Kiddushin 30b has God tell Israel that He created the evil inclination as a wound and Torah as its antidote, warning that one who neglects Torah is handed over to its power yet can rule over it if he wishes. Bava Batra 16a goes further, identifying the Satan, the evil inclination, and the Angel of Death as a single entity that descends to mislead a person into sin and then ascends to accuse him, and Sukkah 52a portrays God slaughtering the evil inclination in the end of days, appearing to the righteous as a mountain and to the wicked as a hair's breadth — all depicting the yetzer as an external adversarial force opposing the will rather than a mere character trait.
Mishneh Torah, Repentance 5:2-3 insists that no one compels a person toward good or evil, that the choice is entirely his own, framing bechirah as untouched by any外部 coercion; Ramban on Devarim 30:6 likewise affirms that from creation onward authority was given to man to act as he wishes, righteous or wicked, so that merit and punishment could attach to his choice. Derashot HaRan 5:16 states plainly that one who denies this bechiri nature denies the entire Torah, and Abarbanel and Sulam on Zohar, Bereshit I 180:2 read the same pasuk as establishing that man was created from both light and darkness precisely so that mitzvot and transgression, and thus bechirah between good and evil, could apply to him.
Several sources describe the yetzer hara as waging an active internal war against the will to do good, functioning as the force that limits free choice in practice even if not in principle. Tanya 9 depicts the divine soul and the animal soul from the kelipah as two kings warring over control of the body, Tanya 27-29 describes the kelipah invading the heart with foreign thought to battle the divine soul especially during prayer, and Tanya 30-31 calls the struggle to break the yetzer's burning passion a genuine test requiring the mind's natural supremacy over the heart. Mesillat Yesharim 1:7-8 similarly places man in the midst of a battlefield of worldly trials, poverty against wealth, tranquility against suffering, while Mesillat Yesharim 11:2-3 notes the yetzer hara intensifies its rationalizations precisely around the sins a person's nature most desires, such as theft and forbidden relations.
Nefesh HaChayim, Gate I 6:6-8 explains that before the sin Adam possessed complete freedom of choice without the powers of evil mixed into him, and that only after the sin did evil become integrated into his being, shaping how the yetzer now functions within bechirah. Da'at Tevunot 72:4-5 adds that the evil inclination exists specifically because God wanted deficiency in man for the sake of free will and reward and punishment — were the soul's light powerful enough, the yetzer hara would not rule over man at all, just as it does not rule over angels.
A cluster of sources from Duties of the Heart, Third Treatise on Service of God 5:19 through Even Sheleimah 4:4, Even Sheleimah 4:16, Even Sheleimah 4:17, and Even Sheleimah 4:1 trace the yetzer hara's tactics for limiting free choice: it first shows love and permitted pleasures, gradually draws the person toward indulgence, presents leniencies, and ultimately dominates once its root desires take hold, so that the person's will no longer feels free even though the root cause lies in bodily and psychological conditioning. Or HaChaim on Vayikra 26:14 likewise describes the yetzer hara's strategy of distancing a person from God gradually, like one who steals a child from his father's house little by little, and Derekh Chayyim 3:1 identifies the yetzer hara as the cause implanted in man that drives him to sin even against his own better judgment. Rabbeinu Yonah on Pirkei Avot 1:14 adds that the yetzer's grip strengthens with habituation, making repentance in old age less complete than in youth, and Sefer Charedim, The Commandment of Repentance 6 describes one who transforms the yetzer hara itself into an ally of the good inclination through complete repentance.
Michtav MeEliyahu (Rav Dessler) and Michtav MeEliyahu (Rav Dessler) directly address how the spiritual yetzer hara operates against free will, explaining that a person may know an act is wrong and still choose to rebel precisely because his will is strong enough to push past clear knowledge, and that bechirah is not simply caused by pleasure but is the chooser's own free selection of the reality he desires. Rav Samson Raphael Hirsch frames even the yetzer hara as stemming from God's love, arguing that this very pull toward evil, exercised through free choice rather than compulsion, is what elevates man above animals, so long as he directs even this inclination toward God's will.
Beit Yaakov, Yitro 76 and Beit Yaakov, Yitro 78 both hold that at the moment a thought first arises in the mind, the person retains free choice to accept good and reject evil, before he becomes submerged in desire and covetousness, after which point divine light can still enter and shape the thought. Mesillat Yesharim 11:51 reinforces that guarding against the first stirrings of improper thought is critical, since impure musings are considered worse than the act itself.
Meshekh Chokhmah, Shoftim 27 addresses a related foundation of bechirah, explaining that divine foreknowledge does not compel human choice because God's knowledge transcends time, leaving the chooser genuinely free. Derekh Hashem, Part One, On the Spiritual Realm:4 similarly describes bechirah as an exception within the created order, where man alone was given power to move himself and the world according to his chosen will rather than by natural necessity.
Several further sources describe the ongoing struggle against the yetzer hara as the engine of merit and renewal. Pirkei Avot 4:1 defines the mighty one as he who conquers his yetzer. Sefat Emet, Bereishit, Vayeshev 2:4-5 teaches that constant wariness of the yetzer hara brings spiritual renewal, while complacency brings stagnation. Sichot Avodat Levi 2:9 and Ba'al Shem Tov, Bereshit 172:1 describe the yetzer hara's strength as proportionate to the greatness of the mitzvah it opposes and as sometimes permitted by Heaven to test a person's resolve. Kaf HaChaim (Palagi) 3:14 and Kaf HaChaim (Palagi), Petichat HaSefer 7 apply the teaching 'if this repulsive one comes to kill you, rise early to kill him first' to the yetzer hara, and Even Sheleimah 8:27 and Shabbat 147b show, respectively, that engagement with Torah's inner dimension blocks the yetzer hara's provocations, while abandoning Torah study for worldly pleasure (as with Rabbi Elazar ben Arakh) lets it prevail. Mishneh Torah, Human Dispositions 6:1 adds that a person's character is naturally drawn after his companions and environment, which bears on how the yetzer gains or loses its footing.
On the side of divine assistance in the struggle, Mishneh Torah, Repentance 6:3-4 cites the prayers of David asking God not to let sin block the path of truth while bechirah remains in his own hand, and Sha'arei Teshuvah 1:1-3 opens by describing the path of teshuva God prepared for those caught in their own iniquities. Tanya, Part I; Likkutei Amarim 1:15 explains the two souls within every Jew, one from the kelipah that generates the negative traits that must be overcome through the divine soul's efforts. Sulam on Zohar, Vaetchanan 75 describes the yetzer tov and yetzer hara as standing respectively at the right and left of a person, with the mezuzah's holiness tipping the balance rightward when he enters his home.
Finally, contemporary halachic writing applies this same bechirah/yetzer framework practically: Rav Eliezer Melamed (Peninei Halakhah, Simchat Habayit U'Virkhato 3:2) states that God created both inclinations and commanded choosing the good, citing Devarim 30:15-20 again as the source of that command, while Rav Eliezer Melamed (Peninei Halakhah, Days of Awe 6:11) describes how a person can become enslaved to his evil impulses — desire, anger, jealousy — losing practical freedom even while his inner will still longs for the good, until teshuva restores his true freedom.