Anyway, back to the subject.
Does having a sinful nature make you a sinner?
Yes, because we are born without God's Spirit and we therefore automatically sin. We do this because our minds are in harmony with the desires of our natures. But here Jesus was born differently:
Christ was born as we are "born again". That simply means He was born with God's Spirit fully controlling His mind. Therefore the sin nature that He assumed, by assuming us, was never allowed to have its way through the power of the Spirit of God. Hence Christ never sinned, not even a thought.
However, the humanity that He was made (at the incarnation) came from Adam. That humanity stood condemned because of indwelling sin (i.e., our bent-to-self or iniquity). Therefore Christ took a condemned humanity, not a guilty humanity. There's a difference. Let me explain:
Let's say you are hitching a ride. A car stops to pick you up, but what you don't know is the driver is under the influence of drugs. Anyway, because he under the influence, he takes a corner too fast and you both die.
Now, who is the sinner in this example?
The driver, the one abusing drugs. He's breaking the law.
Did you die too? Yes! Why, were you guilty? No, you didn't do anything wrong in this example. But because you were in his car his sin condemned you.
Christ is God. He didn't stop being God at the incarnation. At the incarnation Christ as God united Himself to our fallen humanity. Jesus as God got in the car, if you will. Did that make Him a sinner? No! But because He united himself to our fallen life He, as the Son of man, became condemned. Condemned, yes, sinner, no!