2 Kings 16:7

So Ahaz sent messengers to Tiglath-pileser king of Assyria, saying, I am thy servant and thy son: come up, and save me out of the hand of the king of Syria, and out of the hand of the king of Israel, which rise up against me.

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 (Isaiah 7:14; Isaiah 8:4) - that the confederate kings would not prevail against him, Abaz sought aid from the Assyrian monarch.

Saying, I am thy servant, and thy son. This was a plain acknowledgement of his dependent position upon the Assyrian king (cf. 2 Kings 17:4). The same fact may be inferred from various passages, both in Kings and Chronicles; and it can now be proved from the Assyrian monuments, which record the payment of tribute by the tribes of Israel at a much earlier period than any passage of Scripture intimates (see 'Nineveh and Babylon'). To procure an adequate sum for purchasing the succour of the protector's power, Ahaz ransacked the treasures both of the palace and the temple.