Our job on Earth is to prove to God that we have learned from prophet Adam's mistake, and to prove that we indeed are worthy of Paradise.
The proof, of course, will come from obeying God's commands.
Every human being on Earth is forbidden from entering Paradise until he proves that he is worthy of it.
Humans are prisoners in this world. At the moment of their death, God decides their future. The decision is based on their conduct. If they obeyed His commands and proved themselves worthy of Paradise, they will be freed. If on the other hand they disobeyed His commands, they will be transfered to a far worse prison, to stay in there forever.