Let not sin therefore reign in your mortal body, to make you obey its passions (Romans 6:12).

It bears repeating: if you want life, deny yourself (Matthew 16:24–25). Your narcissistic nihilist self will kill you if you do not.

This truth left me trembling again when I heard last week of a respected, seasoned Christian leader who committed suicide after his sexual sin was exposed.

Such a horror is alarming. But no honest person finds it inconceivable. That’s why it’s alarming.

Living with a sin nature is like living with a demon. The devil is not irrational; he’s immoral. He’s a liar, which means he deliberately manipulates reason to serve his own selfish desires. Apart from the regenerating grace of God that’s exactly what we’re like. That’s why Jesus calls unregenerate humans the devil’s children (John 8:44).

When the Father causes us “to be born again to a living hope” (1 Peter 1:3), our “new self, created after the likeness of God” (Ephesians 4:24), comes alive. We begin to desire God and his kingdom.

But just like the kingdom of God in this age breaks out in the midst of, but does not yet destroy, Satan’s kingdom, so our new self comes alive while our “old self… corrupt through deceitful desires” (Ephesians 4:22) still remains. Jesus rules the kingdom of God. Yet this kingdom is harassed by Satan’s kingdom, which controls power structures. Similarly, Jesus rules our new self, even though our old self still has access to our passion triggers — our internal power structures.

That’s what makes fighting sin difficult. It tells us lies that awaken passions and appetites.

For example, a sexually immoral thought begins to rev up our biological sexual engine and then tells us there is no shutting it off until we gratify the craving with the temptation offered. It might feel compelling. But it is a flat out lie. And it is not nearly as hard to deny as it asserts.

Here’s how you know. Let’s say the immoral desire is prompted by a sexually attractive or illicit image on your computer screen. How hard is it to deny that desire if someone else walks in the room? Not hard at all. Close to immediate. The difference is that the old self loves its reputation more than sexual gratification.

Ah, but this exposes the old self’s deception. Sinful passions can be denied, and ruthlessly.

So here’s the point: don’t let sinful passions reign (Romans 6:12). Obey the commands of Christ and not the commands of sinful cravings.

And when you deny yourself, don’t try rationalizing with your fallen self. You already know your weak spots too well.

Rationalizing with your sin is like Joseph trying to rationalize with Potipher’s wife. She’s not interested in the truth. She’s interested in self-indulgent sensual pleasure. She only wants to talk in order to ensnare you. Take Joseph’s example: drop everything and get out of the house. Literally flee for your life.

Jesus promises that if you abide in (believe and keep obeying) his word that you will have full joy (John 15:7, 11). Sin wants to enslave you (John 8:34). Jesus wants to set you free (John 8:36).

Get ready. Your old self is going to command you to sin today. It will pose as your master and sound (and feel) strong. But it’s your former master and its strength is feigned. You don’t have to obey!

Jesus has emancipated you. Say no to slavery and yes to the freedom of the glory of the children of God (Romans 8:21).