The gospel makes it very clear that we are ALREADY crucified with Christ. Past tense. Consider:
“We know that our old self WAS crucified with him” (Rom. 6:6)
“I HAVE BEEN crucified with Christ.” (Gal. 2:20)
“For you HAVE DIED” (Col. 3:3), Etc.
But we also read that our old self is NOT YET dead, and we are in a process of putting it to death:
“if by the Spirit you put to death the deeds of the body, you will live” (Rom. 8:13)
“Put to death therefore what is earthly in you…” (Col. 3:5)
“those who belong to Christ Jesus have crucified the flesh with its passions and desires” (Gal. 5:24), Etc.
In all of these latter examples, the person doing the “crucifying” is the Christian. And he does it by the Spirit inside of him. It is clearly a process that happens over the course of their life. But in the former examples, the crucifixion of the Christian clearly took place at the instant Jesus’ died. In Jesus, we were all crucified. This is not a process, but a past event that we enter into the moment we believe on Chist.
So which one is it? Are we already crucified or is there still a sin nature in us that needs to be crucified? The answer is YES to both.
Yes, we are crucified IN CHRIST. That is, positionally, it is already a done deal. When Christ died, God considered us dead with Him, and we inherit this the instant we receive Him. We are covered in Christ’s death.
However, by CHRIST IN US, that is, the Holy Spirit in us, we work out the putting to death of our sinful nature. It is a process and an experience that is not instantaneous, but takes a whole life of walking by the Holy Spirit–and grows with time.
I think the truth of this duality is expressed concisely in Hebrews 10:14 – “For by a single offering he has perfected for all time those who are being sanctified.” In other words, by Christ’s death, God has ALREADY PERFECTED people who are BEING PERFECTED (i.e. being sanctified). We are positionally perfect in God’s eyes, but, in experience, are being perfected as we walk in His Spirit. We are crucified in Christ (our position) while simultaneously Christ is in us (by His Holy Spirit) leading us into the experience of crucifixion, so that we must “die daily” to our sinful nature by His Spirit.