Either seems appropriate. The sun is quite hot.
Sin can lead to a real hot place.
Capsaicin is that substance found in chili peppers which causes your mouth to burn like hell or the sun. A person might have either of two types of reactions upon a first encounter with capsaicin in the form of biting into a hot chili pepper. The most common is the non-scientist's reaction. Some scientists led by David Julius, an associate professor of cellular and molecular pharmacology at the University of California in San Francisco, recently discovered the receptor that capsaicin grabs onto in order to trigger the painful burning reaction. That breakthrough was reported in the current issue of the journal Nature.