Exodus 21:10

10 If he marries another woman, he must not deprive the first one of her food, clothing and marital rights.

Read Exodus 21:10 Using Other Translations

If he take him another wife; her food, her raiment, and her duty of marriage, shall he not diminish.
If he takes another wife to himself, he shall not diminish her food, her clothing, or her marital rights.
“If a man who has married a slave wife takes another wife for himself, he must not neglect the rights of the first wife to food, clothing, and sexual intimacy.