The Dual Reality of Christ

In Romans seven, Paul says those who belong to Christ Jesus have crucified the flesh with its passions and desires. The idea here is maybe I could crucify the flesh and its passions and its desires apart from Christ. No, you cannot. And so he says in verse 25, if we live by the spirit, let us also keep in step with the spirit. Now what does that look like? What does it look like in this context here?