The origin of saying cross your heart come from?

The phrase "cross your heart" originates from the gesture of crossing one's heart to signify sincerity and truthfulness. This gesture is often associated with a promise or a pledge, suggesting that one is earnest in their intentions. The expression has roots in childhood, where it is commonly used in the context of making a vow or swearing honesty. It reflects a cultural practice of linking physical actions with verbal commitments.