# he walked in the way of the kings of Israel

"King Ahaz acted the same way that the kings of Israel had acted" 

# He even made his son pass through the fire

"He even burned his son to death as an offering to his gods" 

# following the detestable practices of the nations

"copying the disgusting things that the people of other nations did, the nations"

# before the people of Israel

"before the people of Israel who moved into the land"