Definition & Meaning of "the light of one's life"in English

What is the origin of the idiom "the light of one's life" and when to use it?

The idiom "the light of one's life" is a way of expressing deep affection and attachment towards someone or something. The origin of the idiom is not tied to a specific event but is based on the idea of light being associated with positive emotions and warmth. It is used to refer to a person or thing who brings immense joy, happiness, and meaning to someone's existence.