as pure as the driven snow

The phrase "as pure as the driven snow" is an idiomatic expression that is used to describe someone or something that is completely pure, innocent, and untainted. It implies that the person or thing in question is completely free from any kind of corruption, guilt, or impurity, just like freshly fallen snow that hasn't been contaminated or dirtied. It is often used to emphasize the moral or virtuous nature of someone or to describe something in an ideal, flawless state.