He then said to them, “Whoever sends his wife away, without properly divorcing her, and marries another is guilty of being unfaithful to his first wife.
“But here is how I will answer you,” he told them. “Any man who sends his wife away and marries another is guilty of being unfaithful to her, unless she was the one who was not faithful.”
So if she gives herself to another man while her husband lives, she will be guilty of unfaithfulness to her husband. But if her husband is no longer alive, she would not be guilty of unfaithfulness. His death has released her from the law of marriage.
“Whoever sends his wife away, without properly divorcing her, and marries another is guilty of being unfaithful to his first wife. Anyone who then marries her is guilty of marrying another man’s wife.