Abu Hurairah reported the Messenger of Allah (ﷺ) as saying:

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.

حَدَّثَنَا عَبْدُ اللَّهِ بْنُ سَعِيدٍ، حَدَّثَنَا أَبُو خَالِدٍ، عَنْ هِشَامٍ، عَنِ ابْنِ سِيرِينَ، عَنْ أَبِي هُرَيْرَةَ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏

‏ إِذَا دُعِيَ أَحَدُكُمْ فَلْيُجِبْ فَإِنْ كَانَ مُفْطِرًا فَلْيَطْعَمْ وَإِنْ كَانَ صَائِمًا فَلْيُصَلِّ ‏

‏ ‏.‏ قَالَ هِشَامٌ وَالصَّلاَةُ الدُّعَاءُ ‏.‏ قَالَ أَبُو دَاوُدَ رَوَاهُ حَفْصُ بْنُ غِيَاثٍ أَيْضًا عَنْ هِشَامٍ ‏.‏