It is common to hear people say that all sins are the same, but Scripture doesn't agree. Some sins are greater than others. This is clear from what Jesus said to Pilate.
Jesus answered, “You would have no power over me if it were not given to you from above. Therefore the one who handed me over to you is guilty of a greater sin.â€(John. 19:11 NIV)
Note that Jesus did not say that Pilate was without sin in this matter, just that those who handed him over had commited a greater sin.
Also, the same sin can be more serious in some cases than in others.
Jesus said, “If you were blind, you would not be guilty of sin; but now that you claim you can see, your guilt remains. (John 9:41 NIV)
In this case, he does say that they would be without sin
if they were blind. The more you know, the more responsibility you have for doing what's right. Think of this analogy: If a three year old boy says a bad word to his father, the father will probably not punish him right away, but explain to him that that's a bad word and he shouldn't say it to anybody and then let it go at that. But if the same boy says the same word to his father 5 years later, then it's much more serious. By that time, he knows what the word means and should know better than to say it to his father. In that case, his father will punish him.