He had seven hundred wives who were from royal families and three hundred slave women who gave birth to his children. His wives caused him to turn away from God.
Then David knew that the Lord really had made him king of Israel and that he had made his kingdom great. The Lord did this because he loved his people Israel.
Enjoy life with the wife you love. Enjoy all the useless days of this useless life God has given you here on earth, because it is all you have. So enjoy the work you do here on earth.
You ask, “Why?” It is because the Lord sees how you treated the wife you married when you were young. You broke your promise to her, even though she was your partner and you had an agreement with her.