According to Greek mythology, the gods Prometheus and Zeus were at odds with each other because Prometheus had, despite Zeus' wishes, given the gift of fire to humans. Zeus was enraged to see that humans were given the gift of fire, and he punished Prometheus for this by having Hephaestus, the Greek god of blacksmiths, bind him to a rock. The rest of the story describes Prometheus' interactions with the chorus and various other characters, and how he explains his actions and remains defiant even when being threatened by Hermes. There are multiple interpretations of Prometheus' actions and his role in the overall scheme of things, but in each we can see how he fits the definition of the classic trickster who we see in many other myths.
In "Introduction to Modern Mythology," by Thury and Devinney, we read that the trickster is valued as a transformer of culture, or a cultural hero (pp. 228). This can be seen not only in the story of Prometheus, but also in many other myths. A trickster is someone who uses wit and guile to trick those in power and help those who are weak. We also see that a trickster is a liminal figure, one who is on the threshold between two worlds (Thury and Devinney, Introduction to Modern Mythology, pp. 229). We see this in the case of Prometheus who, despite being a titan with the same status as a god, takes the side of the weaker humans. He challenges the authority of Zeus rather than supporting him. .
The major theme we see in the story is how Prometheus, a titan, is punished by Zeus, a god, for helping the humans. This points to a couple different ideas: the gods hold more power than the titans despite being younger, there is a big power gap between the gods and humans, giving the humans divine help is forbidden and is a punishable offense. In addition, in different versions of the story as told by Hesiod (in Theogony) or by Aeschylus (in Prometheus Bound and Works and Days), we see the actions of Prometheus emphasized differently.