Jacob now quotes the succeeding verses of Isaiah 49:24-26 -- see also 1 Nephi 21:24-26.
The Deliverance of the House of Israel
16 For shall the prey (Israel) be taken from the mighty (their enemies), or the lawful captive delivered (that is, will the Lord's covenant people be delivered)?
17 But thus saith the Lord: Even the captives (Israel) of the mighty shall be taken away, and the prey (or captives) of the terrible (tyrannical regimes) shall be delivered; for THE MIGHTY GOD shall deliver his covenant people. For thus saith the Lord: I will contend with them that contendeth with thee (Israel)--
18 And I will feed them that oppress thee, with their own flesh; and they shall be drunken (or out of control) with their own blood (or with their own people) as with sweet wine (that is, Israel's enemies will turn against each other and destroy themselves); and all flesh shall know that I the Lord am thy Savior and thy Redeemer, the Mighty One of Jacob.
[Alan C. Miner, Step by Step through the Book of Mormon: The Covenant Story, Vol. 2; Adapted from David J. Ridges, Isaiah Made Easier / The Book of Revelation Made Easier, 1994]