When one of you receives an invitation (for a meal), he should accept it. If he isn to fasting, he should eat, and if he is fasten, he should pray. Hisham said: The word salat means to pray (for him to Allah). Abu Dawud said: This tradition has also been narrated by Hafs b. Ghiyath from Hisham. (Using translation from Abū Dāʾūd 2460)
"إِذا دُعِيَ أحدُكُمْ إلى طعامٍ فليُجبْ، فإنْ كان مُفْطِرًا فليأكُلْ، وإنْ كانَ صائمًا فليُصَل".