The answer is: Three days and nights

Esther 4:16

Esther’s three-day fast is not just a tactic to prepare herself; it also reflects the depth of Jewish tradition around asserting strength through prayer and self-denial. The act of fasting usually invokes a sense of urgency, spiritual healing, and solidarity with one’s people during times of peril, which is precisely Esther's situation as she seeks to navigate a life-threatening political crisis for her people.

Fasting has a rich lineage throughout the Hebrew Scriptures, found frequently among figures like Moses and even in the Psalms. The three days were likely significant because, in Jewish custom, this timeframe can symbolize thoroughness in seeking out divine favor. There's an interesting echo within this narrative: Jonah, for instance, fasted in the attempt to reach Heaven’s ear for the city of Nineveh, showcasing a dramatic turning point from judgment to mercy.

Esther’s actions are particularly notable because while fasting is often a corporate action, she partakes in it privately before taking a publicly transformative step. Whether or not one articulates belief in divine assistance, the message rings clear—sacrifice, bravery and the advocacy for justice can often formulate paths in seemingly unchangable situations. As the finale reveals Esther is crowned queen of bravery, it sparks a timeless conversation about the roles of individuals in society and the lengths they will go to defend justice and those they love.