Romans 7:2-3
2 For example, by law a married woman is bound to her husband as long as he is alive, but if her husband dies, she is released from the law of marriage.
3 So then, if she marries another man while her husband is still alive, she is called an adulteress. But if her husband dies, she is released from that law and is not an adulteress, even though she marries another man.