Definition & Meaning of "(as|) proud as Lucifer"

What is the origin of the idiom "proud as Lucifer" and when to use it?

The origin of the phrase "proud as Lucifer" can be traced back to religious and literary references. Lucifer, also known as the Devil or Satan, is a figure from Christian theology associated with pride, rebellion, and arrogance. This idiom is used informally to describe individuals who are extremely arrogant or full of pride, often disregarding others.