Deuteronomy 21:14Meaning & Commentary from the Church Fathers

If she displeases you afterwards, you may allow her to go wherever she wishes, but do not sell her for money. When the synagogue of the Jews acted sinfully and laid hands on Christ Himself, tormenting their Lord, it became disliked and unwelcomed, thus being expelled from the sacred and divine sanctuary. Yet she was not sold into bondage, nor completely surrendered to the adversary, nor was she fully at his mercy. Although Israel had drifted from her close communion with Christ, she did not serve idols; she continued to confess and worship the one true God, maintaining her affection for Moses and the law. God did not altogether forsake him due to the honor he once had in His presence.

However, if a man has relations with a captive woman and chooses not to take her as his wife, Moses instructs that she should be set free, granting her freedom as a consequence of their union.