Here is, 1. The attempt of his confederate neighbours, the kings of Syria and Israel, upon him. They thought to make themselves masters of Jerusalem, and to set a king of their own in it, Isa 7:6. In this they fell short, but the king of Syria recovered Elath, a considerable port upon the Red Sea, which Amaziah had taken from the Syrians, Kg2 14:22. What can those keep that have lost their religion? Let them expect, thenceforward, to be always on the losing hand. 2. His project to get clear of them. Having forsaken God, he had neither courage nor strength to make head against his enemies, nor could he, with any boldness, ask help of God; but he made his court to the king of Assyria, and got him to come in for his relief. Those whose hearts condemn them will go any where in a day of distress rather than to God. Was it because there was not a God in Israel that he sent to the Assyrian for help? Was the rock of ages removed out of its place, that he stayed himself on this broken reed? The sin itself was its own punishment; for, though it is true that he gained his point (the king of Assyria hearkened to him, and, to serve his own turn, made a descent upon Damascus, whereby he gave a powerful diversion to the king of Syria, Kg2 16:9, and obliged him to let fall his design against Ahaz, carrying the Syrians captive to Kir, as Amos had expressly foretold, Amo 1:5), yet, considering all, he made but a bad bargain; for, to compass this, (1.) He enslaved himself (Kg2 16:7): I am thy servant and thy son, that is, "I will be as dutiful and obedient to thee as to a master or father, if thou wilt but do me this good turn." Had he thus humbled himself to God, and implored his favour, he might have been delivered upon easier terms; he might have saved his money, and needed only to have parted with his sins. But, if the prodigal forsake his father's house, he soon becomes a slave to the worst of masters, Luk 15:15. (2.) He impoverished himself; for he took the silver and gold that were laid up in the treasury both of the temple and of the kingdom, and sent it to the king of Assyria, Kg2 16:8. Both church and state must be squeezed and exhausted, to gratify this his new patron and guardian. I know not what authority he had thus to dispose of the public stock; but it is common for those that have brought themselves into straits by one sin to help themselves out by another; and those that have alienated themselves from God will make no difficulty of alienating any of his rights.

The king of Assyria hearkened unto him - It is said, Ch2 28:20, that Tilgath-pilneser distressed him, but strengthened him not.
Though he came against the Syrians, and took Damascus, and slew Rezin, yet he did not help Ahaz against the Philistines, nor did he lend him any forces to assist against Israel; and he distressed him by taking the royal treasures, and the treasures of the temple, and did him little service for so great a sacrifice. He helped him a little, but distressed him on the whole.
It appears that, about this time, Pekah king of Israel nearly ruined Judea: it is said, Ch2 28:6, that he slew one hundred thousand valiant men in one day; and that he carried away captive to Samaria two hundred thousand women and children, and much spoil; but, at the instance of the prophet Oded, these were all sent back, fed and clothed, Ch2 28:8-16.

And King Ahaz went to Damascus to meet Tiglathpileser king of Assyria,.... When he heard he was come thither, and had taken it, to congratulate him on the victory, and to give him thanks for his assistance; which place from Jerusalem was one hundred and sixty miles, according to Bunting (q).

and saw an altar that was at Damascus; where, in all probability, he attended at the sacrifice on it along with the king of Assyria:

and King Ahaz sent to Urijah the priest the fashion of the altar, and the pattern of it, according to all the workmanship thereof; not only the size and form of it, but all the decorations and figures on it, with which it was wrought. This Urijah was very probably the high priest, for it can scarcely be thought that Ahaz would write to any other, or that any other priest would or could have complied with his request; and he seems to be the same Isaiah took to be a witness in a certain affair, though he now degenerated from the character he gives of him, Isa 8:2.

(q) Travels, &c. p. 185.

So Ahaz sent messengers to Tiglath-pileser--In spite of the assurance given him by Isaiah by two signs, the one immediate, the other remote (Isa 7:14; Isa 8:4), that the confederate kings would not prevail against him, Ahaz sought aid from the Assyrian monarch, to purchase which he sent the treasures of the palace and temple. Tiglath-pileser marched against Damascus, slew Rezin the king, and carried the people of Damascus into captivity to Kir, which is thought to have been the city Karine (now Kerend), in Media.