The consequences of David's actions arrive through a precise standard of measure for measure. Because his original failure took place in secret, the resulting disaster will unfold in the most public way possible, sprouting directly from his innermost circle. God brings about a devastating tragedy that emerges straight from David's own family and household [מצודת ציון, מצודת דוד, ביאור שטיינזלץ].
The pain of this punishment will be especially severe because David will be entirely aware of it. He will not physically watch the events occur, but he will know exactly what is happening while remaining completely powerless to stop it. This absolute helplessness will make the experience just as agonizing as if it were happening right in front of his eyes [מצודת דוד, רד״ק]. The women involved in this tragedy are specifically ten of David's concubines [מלבי״ם, רד״ק].
These women will be given over to another person. While some understand this individual simply as someone other than David [ביאור שטיינזלץ], other commentators identify him specifically as David's son, Absalom. Absalom is referred to as a peer or companion either because he crowns himself and assumes the status of a king just like his father, or because there is no one closer and more beloved to a man than his own son [מצודת דוד, רד״ק]. This betrayal will happen in the full light of day, exposed for all the public to see, standing in stark contrast to David's hidden deeds [מלבי״ם, מצודת דוד, ביאור שטיינזלץ, רד״ק].
Such a prophecy raises a complex theological question concerning how God can decree that Absalom commit a sin by taking his father's women. The answer lies in a careful distinction between God's actions and human free will [רד״ק]. The promise to bring disaster upon David represents God allowing Absalom to successfully gather power and take control of the kingdom. However, the subsequent act of taking the women stems entirely from Absalom's own free will and personal desires. God does not force him to sin. He merely foresees Absalom's choice and reveals it to David in advance to expose the son's true intentions. Had David not sinned in the first place, God would have protected these women and prevented them from becoming victims of this situation.
Furthermore, the severity of Absalom's actions is rooted in specific boundaries. Technically, a father's concubine is not strictly forbidden to a son by basic law. However, his act is considered a massive failure and deeply immoral because these women belong to a king, making them forbidden to anyone else. Beyond the legal status, the sheer moral ugliness of a son taking his father's concubines makes the act profoundly corrupt [רד״ק].