The angel of course does not give a reason why he wants nothing of Manoah’s food. But the reason could very well be on account of Manoah’s ignorance regarding the angel’s divine identity. Earlier, in Gideon’s interchange with the angel, he seemed to recognize the angel as a divine figure, in his calling the food he wanted to set before the angel as a מִנְחָה (a present
or gift
) (Judges 6:18). Manoah, on the other hand, makes an offer that is quite secular
: he basically says in Judges 13:15, Will you eat with us?
1 Further, the narrator’s remark at the end of Judges 13:16 confirms Manoah’s lack of understanding; he understood the visitor to be someone extraordinary, yet still a man. This difference from Gideon likely explains the different responses of the angel of the Lord: with Gideon he immediately accepts his offer of a מִנְחָה; with Manoah he rejects his offer of a meal, instead instructing him to offer a burnt offering to the Lord.
16 And the angel of the LORD said to Manoah, “If you detain me, I will not eat of your food. But if you prepare a burnt offering, then offer it to the LORD.” (For Manoah did not know that he was the angel of the LORD.)