In fact, it says we can be slaves to righteousness (See: Romans 6:17-18).
That's not what it says. I keep finding this in your assertions, that's why I keep asking that you post the verses themselves, and underline or bold or something where in the verse you are seeing what you assert.
Romans 6:17-18 KJV
17) But God be thanked, that
ye were the servants of sin, but ye have obeyed from the heart that form of doctrine which was delivered you.
18) Being then made free from sin,
ye became the servants of righteousness.
This verse does not say you can become slaves to righteousness, it says, in the KJV, thgat ye became the servants (slaves) of righteousness. This is something that happens when you are immersed into Jesus Christ's death and burial.
Romans 6:11 KJV
11) Likewise reckon ye also yourselves to be dead indeed unto sin, but alive unto God through Jesus Christ our Lord.
He's just told us to reckon ourselves dead to sin, and alive to God, and not because we are to believe a lie.
Romans 6:5-6 KJV
5) For if we have been planted together in the likeness of his death, we shall be also in the likeness of his resurrection:
6) Knowing this, that
our old man is crucified with him, that the body of sin might be destroyed, that henceforth we should not serve sin.
It's not a lie, because we've been crucified with Him, for the purpose of destroying the body of sin - removing it's power, so we don't continue to serve sin.
Romans 6:7 KJV
7) For he that is dead is freed from sin.
And in fact, we've been freed from sin. That's why we are to think of ourselves as being dead to sin.
Romans 6:12-14 KJV
12) Let not sin therefore reign in your mortal body, that ye should obey it in the lusts thereof.
13) Neither yield ye your members as instruments of unrighteousness unto sin: but
yield yourselves unto God, as those that are alive from the dead, and your members as instruments of righteousness unto God.
14) For sin shall not have dominion over you: for ye are not under the law, but under grace.
So then don't yield yourself to sin, but to God. You are alive from among the dead ones, you are now alive unto God, so live that way.
We are crucified with Christ, we are dead to sin and alive unto God, we were slaves of sin, but now we are slaves of righteousness.
We are a new creation, created according to God (patterned after Him) in righteousness and true holiness.
Romans 7:20 KJV
20) Now if I do that I would not, it is
no more I that do it, but sin that dwelleth in me.
This is what changed. We have become dead to sin, and alive to God. We are a new creation, the spirit child of God. The outer man serves sin, the inner man serves God. The flesh is corrupt by sin, the spirit is alive in Christ. We've been reborn.
Much love!