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The title Gebirah, meaning "Great Lady" or "Queen Mother" was a royal title and an office which was bestowed upon the mothers of the Kings of Israel, but limited to those Queens who were mothers of kings in the line of King David. The Gebirah is the most important and influential woman in the royal court and the king's chief counselor. (1 Kings 2:19)
The royal kings of Israel and the House of David had many wives and no single wife of the king had the influence that his mother enjoyed as the chief confidant of her son.
She is "Lady Wisdom" in person.