Then King Ahaz went to Damascus to meet Tiglath-pileser king of Assyria. On seeing the altar in Damascus, King Ahaz sent Uriah the priest a model of the altar and complete plans for its construction.
Though Ahaz had himself sacrificed in high places, on hills, and under every green tree (Kg2 16:4), yet God's altar had hitherto continued in its place and in use, and the king's burnt-offering and his meat-offering (Kg2 16:15) had been offered upon it by the priests that attended it; but here we have it taken away by wicked Ahaz, and another altar, an idolatrous one...
Commenting on 2 Kings 16:10-16
And Urijah the priest built an altar according to all that King Ahaz had sent from Damascus,.... Exactly according to the size, form, figure, and carved work of it, though expressly contrary to the command of God; which fixed both the form and matter of the altar of God, with everything appertaining to it, which he, being high priest, could not be ignorant of, Exo 27:1, &c.
And king Ahaz went to Damascus to meet Tiglath-pileser--This was a visit of respect, and perhaps of gratitude. During his stay in that heathen city, Ahaz saw an altar with which he was greatly captivated. Forthwith a sketch of it was transmitted to Jerusalem, with orders to Urijah the priest to get one constructed according to the Damascus model, and let this new altar supersede...