This verse refutes all sorts of bad doctrine.
1. Reincarnation-if man dies once he can't keep coming back in some other form because he has to die each time before he comes back as something else.
2. Roman Catholism- man dies then the judgement not purgatory. Man doesn't get a chance to better himself after death. It's straight to the judgement.
3. Experiences where people say they died and saw and spoke to their loved ones in heaven and then came back. That is unbiblical. Experience should never trump God's word. The devil is a great counterfeiter.
4. Mormonism- those who have died go straight to the judgement and either to heaven or Hell. Being baptized for a dead person isn't going to change that. Nor can those who are dead have a chance to better their lot before God. Death is the final nail in the coffin.
I'm sure some who read this can think of others. Put them in the comments below.
I'm not picking on the religions mentioned above just because I want to be mean. But it's important that we weigh doctrine against what God's inspired word has to say. It's a matter of eternal life or eternal death and people need to know so they aren't caught up short on judgement day.