2 Kings 16:3-4

16:3 He followed in the footsteps of the kings of Israel. He passed his son through the fire, a horrible sin practiced by the nations whom the Lord drove out from before the Israelites. 16:4 He offered sacrifices and burned incense on the high places, on the hills, and under every green tree.

2 Kings 16:10-12

16:10 When King Ahaz went to meet with King Tiglath-pileser of Assyria in Damascus, he saw the altar there. King Ahaz sent to Uriah the priest a drawing of the altar and a blueprint for its design. 16:11 Uriah the priest built an altar in conformity to the plans King Ahaz had sent from Damascus. Uriah the priest finished it before King Ahaz arrived back from Damascus. 16:12 When the king arrived back from Damascus and saw the altar, he approached it and offered a sacrifice on it.