This is not fun. I'm not enjoying this. But this is foundational to everything that follows. You've got to get this:

In the Sermon on the Mount, Jesus said,

"Beware of false prophets, who come to you in sheep's clothing, but inwardly they are ravenous wolves. You will know them by their fruits. Do men gather grapes from thornbushes or figs from thistles? Even so, every good tree bears good fruit, but a bad tree bears bad fruit. A good tree cannot bear bad fruit, nor can a bad tree bear good fruit. Every tree that does not bear good fruit is cut down and thrown into the fire. Therefore by their fruits you will know them."

Matthew 7:15-20

Paul tells us,

And you He made alive, who were dead in trespasses and sins, in which you once walked according to the course of this world, according to the prince of the power of the air, the spirit who now works in the sons of disobedience, among whom also we all once conducted ourselves in the lusts of our flesh, fulfilling the desires of the flesh and of the mind, and were by nature children of wrath, just as the others. But God, who is rich in mercy, because of His great love with which He loved us, even when we were dead in trespasses, made us alive together with Christ (by grace you have been saved), and raised us up together, and made us sit together in the heavenly places in Christ Jesus, that in the ages to come He might show the exceeding riches of His grace in His kindness toward us in Christ Jesus. For by grace you have been saved through faith, and that not of yourselves; it is the gift of God, not of works, lest anyone should boast. For we are His workmanship, created in Christ Jesus for good works, which God prepared beforehand that we should walk in them.

Ephesians 2:1-10

Apart from regeneration by the Holy Spirit, man is absolutely morally unable to do good. Let me just blast a few more out:

Job 14:4 - Who can bring a clean thing out of an unclean? There is not one.
Job 15:14-16 - What is man, that he can be clean? Or he that is born of a woman, that he can be righteous? Behold, God puts no trust in his holy ones, and the heavens are not clean in his sight; how much less one who is abominable and corrupt, a man who drinks iniquity like water!
We start young, too:
Psalm 58:3 - The wicked go astray from the womb, they err from their birth, speaking lies.
Psalm 51:5 - Behold, I was brought forth in iniquity, and in sin did my mother conceive me.
Genesis 8:21 - And when the LORD smelled the pleasing odor, the LORD said in his heart, "I will never again curse the ground because of man, for the imagination of man's heart is evil from his youth; neither will I ever again destroy every living creature as I have done."
Proverbs 4:23 - Keep your heart with all vigilance; for from it flow the springs of life.
Jeremiah 17:9 - The heart is deceitful above all things, and desperately corrupt; who can understand it?

Listen to Paul again,

Therefore, since we have this ministry, as we have received mercy, we do not lose heart. But we have renounced the hidden things of shame, not walking in craftiness nor handling the word of God deceitfully, but by manifestation of the truth commending ourselves to every man's conscience in the sight of God. But even if our gospel is veiled, it is veiled to those who are perishing, whose minds the god of this age has blinded, who do not believe, lest the light of the gospel of the glory of Christ, who is the image of God, should shine on them. For we do not preach ourselves, but Christ Jesus the Lord, and ourselves your bondservants for Jesus' sake. For it is the God who commanded light to shine out of darkness, who has shone in our hearts to give the light of the knowledge of the glory of God in the face of Jesus Christ.

2 Corinthians 4:1-6

Flee also youthful lusts; but pursue righteousness, faith, love, peace with those who call on the Lord out of a pure heart. But avoid foolish and ignorant disputes, knowing that they generate strife. And a servant of the Lord must not quarrel but be gentle to all, able to teach, patient, in humility correcting those who are in opposition, if God perhaps will grant them repentance, so that they may know the truth, and that they may come to their senses and escape the snare of the devil, having been taken captive by him to do his will.

2 Timothy 2:22-26

Jesus answered them, "Most assuredly, I say to you, whoever commits sin is a slave of sin.

John 8:34

Before the Fall, man could freely choose to do good or to do evil.
After the Fall, man became a slave of sin. His will operates within this bondage. He can do whatever he wants (wills) to do, however that will can only choose to do evil.
A change must come.
When the Holy Spirit regenerates a fallen heart, man can once again choose to do good or to do evil.
Every regenerated man will one day become a glorified man. In that glorified state, he will then be free to choose good, and only good.
This regeneration is powerful. As Paul says,

Therefore I also, after I heard of your faith in the Lord Jesus and your love for all the saints, do not cease to give thanks for you, making mention of you in my prayers: that the God of our Lord Jesus Christ, the Father of glory, may give to you the spirit of wisdom and revelation in the knowledge of Him, the eyes of your hearts being enlightened; that you may know what is the hope of His calling, what are the riches of the glory of His inheritance in the saints, and what is the exceeding greatness of His power toward us who believe, according to the working of His mighty power which He worked in Christ when He raised Him from the dead and seated Him at His right hand in the heavenly places, far above all principality and power and might and dominion, and every name that is named, not only in this age but also in that which is to come. And He put all things under His feet, and gave Him to be head over all things to the church, which is His body, the fullness of Him who fills all in all.

Ephesians 1:15-23

Feeling depraved? Hold that thought.

Grace is coming.