A woman came to the Messenger of Allah (ﷺ) and said: "I have a co-wife. "Is there any harm for me if I give her the false impression of getting something from my husband which he has not in fact given me?" The Messenger of Allah (ﷺ) said, "The one who creates a false impression of receiving what one has not been given is like one who wears two garments of falsehood."

[Al-Bukhari and Muslim].