‘ And the Angel of Yahweh said to Manoah, “Though you detain me, I will not eat of your bread, and if you will make ready a burnt offering, you must offer it to Yahweh.” For Manoah did not know that he was the Angel of Yahweh.'
The Angel replied that He would not eat food even if it were brought. This would often be a sign of hostility, but in this case should rather have suggested to Manoah the urgency of his errand and that he had come from an untainted place (compare 1 Kings 13:8-9; 1 Kings 13:16-17). He then suggested that instead he should prepare a burnt offering for Yahweh, as a sign of worship, dedication and obedience. His gratitude was due to Yahweh. We can compare with this where Gideon prepared a meal but it became a burnt offering (Judges 6:20-21).
“Manoah did not know that he was the Angel of Yahweh.” From Judges 13:8 we know that Manoah thought that the visitor was a ‘man of God', a prophet, and he still held that view. Thus the offer of the meal. His wife may still not have been sure Who the visitor was, or even what God He represented. Thus the Angel's reply clarified the situation for the wife, and directed Manoah as to where his main responsibility lay. Honour was not to be paid to the messenger but to God Himself.