Slave to sin or slave to righteousness?

I’ve been reading Romans 3 – 10 over and over and I’ve gotten hung up on what seems like a contradiction when I read Romans 6 – 8 in sequence. This portion of his letter to the Romans is extraordinary when you compare it to what Paul says before and afterwards.

In Romans 7:18-19 Paul was unable to do the good that he wanted to and forced to do evil but he’s comfortable telling the Romans in chapter 6
What shall we say then? Shall we continue in sin that grace may abound? Certainly not! How shall we who died to sin live any longer in it? - Romans 6:1-2

In Romans 7:23-25 sin was dwelling in Paul, holding his body captive and forcing him to sin but the chapter before he wrote this… “knowing this, that our old man was crucified with Him, that the body of sin might be done away with, that we should no longer be slaves of sin. For he who has died has been freed from sin.” – Romans 6:6-7

And

Therefore do not let sin reign in your mortal body, that you should obey it in its lusts. And do not present your members as instruments of unrighteousness to sin, but present yourselves to God as being alive from the dead, and your members as instruments of righteousness to God. For sin shall not have dominion over you, for you are not under law but under grace. – Romans 6:12-14

Did Paul as a Christian once justified, crucified with Christ and walking in the Spirit serve God with his mind but continue to serve sin with his body?

Or do you not know that as many of us as were baptized into Christ Jesus were baptized into His death? Therefore we were buried with Him through baptism into death, that just as Christ was raised from the dead by the glory of the Father, even so we also should walk in newness of life. – Romans 6:3-4
Likewise you also, reckon yourselves to be dead indeed to sin, but alive to God in Christ Jesus our Lord. – Romans 6:11

Do you not know that to whom you present yourselves slaves to obey, you are that one’s slaves whom you obey, whether of sin leading to death, or of obedience leading to righteousness? But God be thanked that though you were slaves of sin, yet you obeyed from the heart that form of doctrine to which you were delivered. And having been set free from sin, you became slaves of righteousness. – Romans 6:16-18

How can Paul tell the Romans to use their bodies as slaves of righteousness if he himself wasn’t set free from sin?

I speak in human terms because of the weakness of your flesh. For just as you presented your members as slaves of uncleanness, and of lawlessness leading to more lawlessness, so now present your members as slaves of righteousness for holiness. – Romans 6:19
But now having been set free from sin, and having become slaves of God, you have your fruit to holiness, and the end, everlasting life. For the wages of sin is death, but the gift of God is eternal life in Christ Jesus our Lord. – Romans 6:22-23

The only possible explanation I can think of is that it isn’t a contradiction but a contrast. Its possible that Paul presented the truths out of sequence to highlight the differences between our old lives and our new lives in Christ. In Romans 6 he clearly states the believer is dead to sin and in Romans 7 he uses an illustration of a woman married to one man becoming free to marry another when her first husband dies. He describes the sinner as locked in a struggle with sin. And then in chapter 8 the believer is once again not controlled by the sinful nature but by the Spirit of God.

You however, are controlled not by the sinful nature but by the Spirit. If the Spirit of God lives in you. And if anyone does not have the Spirit of Christ, he does not belong to Christ. But if Christ is in you, your body is dead because of sin, yet your spirit is alive because of righteousness. And if the Spirit of Him who raised Jesus from the dead is living in you, He who raised Christ from the dead will also give life to your mortal bodies through His Spirit, who lives in you. - Romans 8:9-11