Here "walking" is an idiom that refers to how he lived and reigned as king. At this time in history, the recent kings of Israel had been evil kings. The full meaning of this statement can be made clear. AT: "Jehoram was an evil king, just as other kings of Israel who ruled before him had been" (See: [[rc://en/ta/man/translate/figs-idiom]] and [[rc://en/ta/man/translate/figs-explicit]])
Here the "house" of Ahab refers to the members of Ahab's family and his recent descendants. Ahab is Jehoram father-in-law. AT: "the same as the rest of the family of Ahab was doing" (See: [[rc://en/ta/man/translate/figs-metonymy]])
The sight of Yahweh represents Yahweh's judgment or evaluation. AT: "what was evil in Yahweh's judgment" or "what Yahweh considers to be evil" (See: [[rc://en/ta/man/translate/figs-metaphor]])
"since Yahweh had told David that he would always give David descendants." This refers to Yahweh's promise to David that his descendants would always rule Judah. The full meaning of this statement can be made explicit. AT: "since he had told David that his descendants would always rule Judah" (See: [[rc://en/ta/man/translate/figs-explicit]])