If we want to defeat the lusts of the flesh, we need to see ourselves as God sees us in the Spirit. Walking by the Spirit and not the flesh is how we defeat the lusts of the flesh.

This is who you are Christian.

If we keep on looking at our flesh in the mirror and trying to perfect our flesh by our flesh, we will never walk by the Spirit and defeat the lusts of the flesh. The flesh cannot perfect the flesh.
You foolish Galatians, who has bewitched you, before whose eyes Jesus Christ was publicly portrayed as crucified? This is the only thing I want to find out from you: did you receive the Spirit by the works of the Law, or by hearing with faith? Are you so foolish? Having begun by the Spirit, are you now being perfected by the flesh? Did you suffer so many things in vain—if indeed it was in vain? So then, does He who provides you with the Spirit and works miracles among you, do it by the works of the Law, or by hearing with faith? Gal 3:1-5NAS

We are to see the flesh as crucified, dead an unable to help us at all. We have died with Christ.

You have died with Christ, and he has set you free from the spiritual powers of this world. So why do you keep on following the rules of the world, such as, “Don’t handle! Don’t taste! Don’t touch!”? Such rules are mere human teachings about things that deteriorate as we use them. These rules may seem wise because they require strong devotion, pious self-denial, and severe bodily discipline. But they provide no help in conquering a person’s evil desires (flesh). Col 2:20-23 NLT

Jesus poured out His blood for the New Covenant of grace and truth, replacing the Old Covenant letter of the law of Moses. Believers are exclusively under the New Covenant, the last will and testament of Jesus that began after the cross.