Called to contend by fire; Septuaguint, ἐκάλεσε τὴν δίκην ἐν πυρί, "called for judgment by fire;" Vulgate, vocabat judicium ad ignem. God called the people to try their cause with him by sending fire as a punishment among them (comp. Isaiah 66:16; Ezekiel 38:22); and in the vision the fire is represented as so vehement that it devoured the great deep, drank up the very ocean itself (Genesis 7:11; Isaiah 51:10); or the subterranean fountains and springs, as Genesis 49:25. And did eat up a part; τὴν μερίδα κυρίου. This version takes eth-hacheleq as the "inheritance" or "portion" of the Lord, i.e. the land of Israel (Jeremiah 12:10); but Canaan is nowhere called absolutely "the portion;" nor were the ten tribes specially so designated. Rather, the portion (not a part) is that part of the land and people which was marked out for judgment. The particular calamity alluded to is the second invasion of Tigiath-Pileser II, when he conquered Gilead and the northern part of the kingdom, and carried some of the people captive to Assyria (2 Kings 15:29).
The intercession is the same as in Amos 7:2, except that the prophet says cease instead of "forgive;" and in effect the tide of war was rolled back from Israel, and Samaria itself was spared for the time.