Why was Noah never condemned by God for becoming drunk and committing the sin of incest? And God used him to build the ark.
You're mixing events. Noah was a righteous man (Genesis 7:1). He was saved when he obeyed God and built an ark. But it wasn't until years later that he got drunk and was naked in his tent (Genesis 9:21). The Bible doesn't say he committed incest. The two cases of incest that I can think of are by Lot's daughters (Genesis 19:30-38) and Amnon (II Samuel 13).
But the question was why wasn't Noah condemned for his drunkenness. In a way he was, two of his sons refused to look at him while he was drunk and naked (Genesis 9:23). Clearly, they knew his condition to be wrong. And it isn't that God doesn't make it clear that drunkenness is sinful (for example, Provers 20:1). So just because the Bible might not record all the consequences that came upon Noah because of his sin, it doesn't imply that nothing happened to him.
But there were consequences. Because Noah got drunk, he laid naked in his tent. Because of that, his son Ham gave in to the temptation to mock his father. Because of that Ham lost his blessing and the descendants of his son Canaan were prophesied to be slaves. Quite a long-reaching effect for overindulging.
The same is true of you and me. When we sin, we aren't likely to get struck by lightning the next moment. But those sins often have consequences we don't immediately realize or see. Just because we are immediately condemned, it doesn't mean what we did was acceptable to God.
Thanks. You are right, I was confused. I just heard someone say that in a sermon, and I send the email without looking things up and examining them for myself, which is awful, I know. But thanks for setting things straight.