Albert Barnes Commentary Daniel 11:26

"Yea, they that eat of his dainties shall destroy him, and his army shall overflow; and many shall fall down slain." — Daniel 11:26 (ASV)

Indeed, they that feed of the portion of his meat shall destroy him—Those of his own family; those who are nourished at his table; those who are his cabinet counselors, and professed and confidential friends. The meaning is that they would prove treacherous and unfaithful.

This is by no means improbable. Antiochus was powerful and had seized Pelusium, Memphis, and the fairest portions of Egypt. He was also in possession of the person of the lawful king and had a fair prospect of subduing the whole country. In these circumstances, nothing would be more natural than that the very inmates of the palace—the persons around the reigning king—should begin to doubt whether he could hold out and should be disposed to make terms with the invader.

And his army shall overflow—The connection here requires us to understand this as referring to the army of the king of Egypt. The meaning seems to be that his forces would be great and would spread themselves out like overflowing waters, but that notwithstanding this, many of them would be slain.

And many shall fall down slain—In battle. Notwithstanding the army would be numerous and would, as it were, spread over the land, it would still not be sufficient to keep out the invaders, but many of them would fall in the field. The account in 1 Maccabees 1:18 is that Ptolemy was afraid of him (Antiochus) and fled; and many were wounded to death.