Angels take a meal with Abraham

 Crispin H. T. Fletcher-Louis[1] points out how Luke makes sure that the post resurrection Jesus has a bite to eat. He claims that this would prove that Jesus was not an angel/spirit according to the popular notion of angels at that time.

Luke 24:41RSV And while they still disbelieved for joy, and wondered, he said to them,  “Have you anything here to eat?”  42 They gave him a piece of broiled fish,  43 and he took it and ate before them.

Jesus “proves” he is more human than a spirit by having them touch his body and eating some fish before their eyes. The later action relies on the widespread contemporary belief that angels do not eat - or at least they don’t eat ordinary food. [1]

Right in the same context,  Fletcher-Louis compares Luke’s Road to Emmaus pericope to Abraham’s hospitality for the three men at the Oak of the Mamre Gen. 18 which appears to contradict the notion that Angels do not eat.

Gen. 18:8b … and he stood by them under the tree while they ate. 
והוא־עמד עליהם תחת העץ ויאכלו
αὐτὸς δὲ παρειστήκει αὐτοῖς ὑπὸ τὸ δένδρον

[1]Crispin H. T. Fletcher-Louis, Third Oxford Lecture on the Development of Christology; Narrative Christologies: The Transfiguration and Post-Resurrection Stories