Caliban thinks Trinculo is one of Prospero's spirits

Lo, now, lo!
Here comes a spirit of his, and to torment me
For bringing wood in slowly. I’ll fall flat;
Perchance he will not mind me.

– William Shakespeare

The Tempest, Act 2, Scene 2. Caliban spots Trinculo, one of the survivors of the shipwreck. He believes that Alonso’s court jester is a spirit sent by his master and sorcerer Prospero to torment him for bringing wood in too slowly.