Walk through Amos, verse by verse, with the great Bible Commentaries of Matthew Henry (1662 - 1714) & Adam Clarke (1760 - 1832)
9:8
Behold, the eyes of the Lord GOD are upon the sinful kingdom, and I will destroy it from off the face of the earth; saving that I will not utterly destroy the house of Jacob, saith the LORD. KJV
{Lo! the eyes of the Lord God be on the realm sinning (Lo! the eyes of the Lord God be upon the sinning realm, or upon this sinful kingdom), and I shall all-break it from (off) the face of [the] earth;
nevertheless I all-breaking shall not all-break the house of Jacob, saith the Lord.} Wycliffe's Bible
The eyes of the Lord God are upon the sinful kingdom - The kingdom of Israel, peculiarly sinful; and therefore to be signally destroyed by the Assyrians.
I will not utterly destroy the house of Jacob - The race shall not become extinct: I will reserve them as monuments of my justice, and finally of my mercy.
I will not utterly destroy the house of Jacob - The race shall not become extinct: I will reserve them as monuments of my justice, and finally of my mercy.