Verses 30 and 33 bracket and set forth Ahab's unusual wickedness with special emphasis. The writer had just written that Omri was the worst king so far (v. 25), but now he said Ahab exceeded him in wickedness. For Ahab, the fact that Jeroboam's cult deviated from the Mosaic Law was "trivial"(v. 31).169
The writer held Ahab responsible for marrying Jezebel. This was fair because even in arranged marriages in the ancient world the candidates, especially the son, in most cases had the right of refusal. Ahab and Jezebel became the most notorious husband and wife team in Scripture.170
Ahab's greatest sin, however, was that he brought the worship of Baal--the worship of the native Canaanites whom God has commanded Israel to exterminate--under the official protection of his government. Jeroboam had already refashioned Yahweh worship departing from what Moses had prescribed. Ahab went one step further. He officially replaced the worship of Yahweh with idolatry (cf. 18:4). This was a first in Israel's history.
"This represents a quantum leap in the history of apostasy."171
The temple and altar to Baal that Ahab erected in Israel's capital symbolized his official approval of this pagan religion. Remember the importance of David's bringing the ark into Jerusalem and Solomon's building a temple for Yahweh and what that symbolized?
Verse 34 may at first seem to have no connection with anything in the context. Perhaps the writer included it to show that as God had fulfilled His word about Jericho, so it would be in Ahab's case. Ahab was establishing paganism that God had already said He would judge. Similarly Hiel had tried to set up a city that God had previously said the Israelites should not rebuild (cf. Josh. 6:26). The building of Jericho is also a tribute to Ahab's apostasy since he must have ordered or permitted Hiel to rebuild the city in spite of Joshua's long-standing curse.
"The foundation sacrifice, revealed by modern archaeology, is probably what was involved. The children named were probably infants, dead or alive, placed in jars and inserted into the masonry, propitiating the gods and warding off evil."172