Note 2 at Acts 24:15: Paul not only denies any sedition and states that he is accused over religious matters (see note 1 at v. 14, this page), he goes on to specify the main religious issue in question, the resurrection. By mentioning the resurrection, he was rekindling the rivalry between the Pharisees and the Sadducees (see note 4 at Acts 23:6, p. ???) that had got him "off the hook" before.

Note 3 at Acts 24:15: There are some people who believe in only a partial resurrection. There are different variations of this belief but usually they believe only a select group will be resurrected to eternal life and the rest of the dead are just non-existent. Paul clearly did not believe this. He believed that the just and unjust would both be resurrected.