Compiled by Imam Yahya ibn Sharaf al-Nawawi
عن أبى هريرة رضى الله عنه قال: قال رسول الله صلى الله عليه وسلم : "إذا دعي أحدكم ، فليجب، فإن كان صائما فليصل، وإن كان مفطراً فليطعم" .((رواه مسلم))
The Messenger of Allah (ﷺ) said, "When any of you is invited to a meal, he should accept the invitation. If he is observing Saum (fasting), he should supplicate for the betterment of the host and if he is not fasting, he should eat." [Muslim].