torch

carry a torch for feel (especially unrequited) love for.

1996TV Times A dentist carrying a torch for the local 'strawberry blonde' wonders if he married the right woman.

hand on (or pass) the torch pass on a tradition, especially one of learning or enlightenment.

☞ The image here is that of the runners in a relay passing on the torch to each other, as was the custom in the ancient Greek Olympic Games. The tradition of the torch relay is preserved as a prelude to the modern Olympics, with a team of runners carrying the Olympic torch vast distances across various countries until the site of the Games is reached.

put to the torch (or put a torch to) destroy by burning.