I sent this email today and, boy, did it fire me up and exhort me. May it do the same for you:
I really want to answer your question, and I only see one in your email. "How in Jesus' name do I live holy?!"
I have an answer because I, of course, have faced the same battle you describe. Once you find out that the evangelical version of salvation by faith alone--the "free ticket to heaven" doctrine--is bogus, then what replaces it? Works? In fact, yes, works replace faith alone (James 2:24), but it is critically important not to turn works into law. There is no law that can produce righteousness (Gal. 3:21). We will be judged by our works, but we will never obtain works by the hearing of the law, whether it is the Law of Moses or the law of some denomination or the law we put upon ourselves.
To me, the most comforting verse in the Bible is, "For we, through the Spirit, await the righteousness that comes by faith" (Gal. 5:5).
Once we figure out that the evangelical plan of salvation is bogus, our biggest problem is that we still think God our Father is a God of rules, law, and condemnation. Honestly, we still think God is stupid. We think he is shocked by sin and surprised at human weakness. We think he is appalled that our ways are lower than his and our thoughts lower than his. We think he doesn't realize that we are human and weak.
Jesus is going to save us, and both he and his Father know that we need to be saved! He knows that we are drowning in sin. He knows that we have no self-control. This is why he said that we can do nothing without him (Jn. 15:5). We live "by his life" (Gal. 2:20) and "by his Spirit" (dozens of verses, but Rom. 8:13 is a good one).
If you don't have hopelessness in yourself, you will never have the right kind of trust in God, nor power to walk in the Spirit.
So, first, hopelessness in your flesh. You should not be surprised you are failing because God is not surprised. You are not the committed Christian you thought you were because you have a wrong picture of what a committed Christian is. Let's talk about walking in the Spirit and walking in the light.
Walking in the Spirit has everything to do with your mind. After telling us that we will be delivered from the Romans 7 life by the sacrifice of Christ and gift of the Holy Spirit (Rom. 8:1-4), Paul writes, "The mind set on the Spirit is life and peace." That is followed quickly by, in so many words, "the mind set on the flesh is death." There is such a thing as a committed, self-controlled Christian. The committed, self-controlled Christian runs to his (or her) Father quickly, hopeless in his or her own strength, not fighting temptation but fleeing (2 Tim. 2:22) and escaping (1 Cor. 10:13) it. Because the one who walks in the Spirit is the one who sets his mind on the things of the Spirit, the only place he or she knows to flee is to Jesus. We look to Jesus as our example (Heb. 12:1-2), we look to heaven where Jesus, our life, sits at the right hand of the Father. We set our mind on spiritual things. We contemplate how we are seated in the heavenlies with King Jesus at the right hand of the Father (Eph. 2:7, I think).
When we do something other than that, and wind up giving into temptation, we lament and wail and mourn, and we humble ourselves under the mighty hand of God, not because God won't forgive us otherwise, but because that is the place we were always supposed to be anyway, under the MIGHTY hand of God. God is mighty when he judges, but he is even more mighty when he forgives AND delivers. This is the great work of God, that he can transform weak humans into men and women of God. Elijah had passions like we do (James 5:17), but he was a mighty man with God, praying and stopping the rain for 3 years, then praying again and the rain came back. Why? It was not because he was stronger than us; that is what James is saying. Instead, he had his mind on God more than we do.
Be transformed by the renewing of your mind (Rom. 12:1-2). Turn your mind to spiritual things, to Jesus, to the glories that await us, to the hope of eternal life, to the presence of God. Say honestly, "One thing have I desired, and that will I seek after, that I may dwell in the temple of the Lord, to behold your beauty and inquire at your temple" (I forget where this is).
Paul had mighty weapons of warfare, and look at what they did. They tore down strongholds, cast down IMAGINATIONS, and every high thing that exalts itself against the KNOWLEDGE of God, bringing every THOUGHT into captivity to the obedience of Christ (2 Cor. 10:4-5). What are you thinking about? That is what you will be doing. The mind set on the flesh cannot obey God; it is the enemy of God (Rom. 8:5-8).
We are in a war, friend, but we are not fighting alone. If you will give God your thoughts, he will transform them, step by step and day by day, even minute by minute. It is as we "behold" our God that we are transformed into that image from glory to glory, even as by the Spirit of the Lord (2 Cor. 3:18). The one who has begun a good work in you--and he has begun a good work in you because you are longing for righteousness--will be completing it until the day of King Jesus (Php. 1:6).
Ok. Let's talk about walking in the light.
If we walk in the light, we have fellowship with one another, and the blood of Jesus Christ purifies us from every sin (1 Jn. 1:7). That's pretty awesome. How do we walk in the light?
Light is that which exposes (Eph. 5; Jn. 3:19-21). Don't be confused about John 3:19-21. There the evil man hides in the darkness, not wanting his deeds to be exposed. It is easy, then, to suppose that it is the righteous man who brings his deeds to the light so that they can be seen to have been done in God. There are, however, NO RIGHTEOUS MEN except those who have been made so by God's Spirit. Don't hide in the darkness. Take your pitiful self into the light, and expose your rotten deeds to the Light! The Light, according to 1 John 1:7, is going to catharize you. It will heal, cleanse, and purify those wicked ways of yours. Get in the light! Get in the light! Get in the light! Confess your sins; do not hide, especially from God. In his light is purification. The heat of the light, exposing you as naked, miserable, and wretched, will cleanse you. The FRUIT of the light is goodness, righteousness, and truth (Eph. 5, somewhere around verse 10). You can achieve goodness and righteousness by exposing your deeds to the light.
You are being created in King Jesus and by God to do good works. You are not being transformed by your will or your strength or your self-control. As you surely realize, those are all pitiful. Either you are living in the light, setting your mind on things above and on things of the Spirit, and you are becoming righteous by faith, or you are thinking about your flesh, looking at your lack of self-control, and thus living as an enemy of God. Change your mind! Set it on things above! This is more important than food or drink, more important than your family. Get in the presence of God, and you will receive the righteousness that comes by faith.
You did catch, right, that in the light, the blood of Jesus continually cleanses us of our sins? When we are in the light, there is no hiding from God. We rush boldly to the throne of grace because we know that there is mercy, forgiving our sin, and grace to help in time of need. Grace is horribly misdefined and mistaught in modern Christianity. Under grace, sin does not have power over you (Rom. 6:14). The grace that saves teaches you to deny ungodliness and worldly lusts and live soberly, righteously, and godly in this present age (Tit. 2:11-12). Run to the throne of Grace! It is the best place on earth and in heaven because forgiveness of sin and power over sin is there, much the same as what is said about walking in the light.
These all tie together. What are you doing with your mind? What are you thinking about? Are you dragging your flesh to the light, in great humility exposing your weaknesses and sins, and awaiting the righteousness that comes by faith, which happens by the power of God when you kneel before his throne? This is the route to holiness, to sanctification, and to its end, eternal life (Rom. 6:22).
I hope that helps. I'll send you this email or something like it, over and over if you need it, but best of all is to have friends around who are reminding you and each other of these things (Heb. 3:13; 10:24-25). Read those two passages in Hebrews. We are fighting together, and our warfare is mostly in the mind, exhorting and encouraging each other to focus on spiritual things, to focus on Jesus, to run to the Father, to have our first desire to be dwelling in the temple of God, beholding his beauty and inquiring of him.