It's interesting to me that in that verse in the op, God says he will destroy them. What does that mean really. Kinda sounds like they get the boot to me if all they come to heavens door with is hay, wood and straw.
I understand where one would think that but we need to look at all other scriptures that talk about the security of the believer. The word "destroy" in the OP means "corrupt".....not in the total annihilation sense and you are banned from heaven forever. Works-based salvationists would take that as God not allowing you in heaven. This is "reading" into the scripture. ( not saying you are doing that here..)
I'm taking that God will destroy = to mean that He will allow corruption to happen to some of these people who have false teachings that are in fact defiling the temple of God which is His body. He would withdraw protection and either chastise them or for in some cases - them dying physically here in this earth.
It is an obscure passage and needs to be interpreted in light of all the other clear scriptures.
Getting to heaven is not based on us - it is based on what Christ has done for us and we have His righteousness - not by doing deeds of righteousness. This is the whole gospel message.