when does he say that??????????????

@sarumanusson, he says it in Lucifer Rising.

John had issues and he wasn't the best father in the world. He did the best he could but the way he raised those boys damaged them for life. Bobby wasn't necessarily saying that John was without merit- he was just saying that Dean was a better man. And I agree. John was a close-mouthed, secretive control-freak who pushed Sam away. Bobby was telling Dean not to make those same mistakes. That he didn't have to be his father, that he could reach out to Sam. Dean is a better man than John. That doesn't mean that John was a horrible person.

This is why I highly dislike Bobby now. You don't just replace the man you spent YEARS with, with someone new, and fail to remember your own father. Yes, John made HUGE HUGE AWFUL mistakes. But this was uncalled for on a lot of different levels.

I agree with fanfly.

Bobby wasn't telling Dean for forget his father, or to stop caring about him. He was warning him not to become his father -- the man whose sole priority was hunting the "big bad." The man who left his young children in a hotel room alone for days, who missed Christmases, birthdays, Thanksgiving. The man who put so much pressure on Dean (who was still a kid himself) to step up and be the parent. The man who would rather his son not be a part of his life at all then sit down and work out all the issues they had.

I am agree with @fanfly and @bri-marie

He wasn't saying that in the level like to forget his dad, that John was bad father. He just said him not to become like him, not to do everything just for hunting, just for revenge. Because Dean is better man, he was so small and he needed to take for Samm and for John too. He always needed to be the strong one, when everyone else just could break, he couldn't because John kinda didn't allow him that, he couldn't do that, he couldn't be weak, he needed to be strong for Sammy. Dean was the one who always neded to make everything right when John messed up, he needed to make Sammy still love and trust in his dad even John always missed every important thing. John pushed them both away, but mostly it was with Sam, he pushed him away. And just like @fanfly said Bobby was saying that to Dean because Dean was making the same mistake.

Not to that extreme. But he tells Dean not to make the same mistakes, and I totally agree with him in that moment

John wasn't perfect but no parent is. I don't think Bobby should have said what he did.

Bobby was absolutely right in my opinion, if not so much for anything else at least for John's behavious towards Sam. He was a little harsh but all he wanted was to shaken up Dean, so this is completely understandable.