Definition & Meaning of "jot (and|or) tittle"

What is the origin of the idiom "jot and tittle" and when to use it?

The idiom "jot and tittle" originates from the Bible, specifically from the New Testament in the Gospel of Matthew 5:18 (King James Version): "For verily I say unto you, till heaven and earth pass, one jot or one tittle shall in no wise pass from the law, till all be fulfilled." In this context, "jot" refers to the smallest letter in the Hebrew alphabet (the letter yod), and "tittle" refers to a tiny stroke or mark used in the writing of certain letters. This phrase is used to emphasize extreme precision or attention to the smallest details, often in the context of rules, laws, or instructions. It signifies that every tiny element or nuance is being carefully considered or followed.