Charles Ellicott Commentary 1 Kings 15:18

"Then Asa took all the silver and the gold that were left in the treasures of the house of Jehovah, and the treasures of the king`s house, and delivered them into the hand of his servants; and king Asa sent them to Ben-hadad, the son of Tabrimmon, the son of Hezion, king of Syria, that dwelt at Damascus, saying," — 1 Kings 15:18 (ASV)

Sent them to Ben-hadad. —This shows that Syria, recovering its independence at the fall of Solomon’s empire, was already attaining the formidable power which so soon threatened to destroy Israel altogether. The Ben-hadad of the text is the grandson of Hezion, who must be the Rezon of 1 Kings 11:23. Already, as we gather from the next verse, there had been alliances between Syria and Judah in the preceding reign. Now it is clear that Baasha had attempted to supersede these with a closer alliance—possibly, like Pekah in later times (2 Kings 16:5–6), desiring to strengthen and secure himself against invasion by the subjugation of Judah.

Asa naturally resolved to bribe Ben-hadad with presents to prefer the old alliance to the new; but he went beyond this, and proposed a combined attack on Israel, for the first time calling in a heathen power against his "brethren, the children of Israel." It was an expedient which, though it succeeded for its immediate purpose, yet both as a desperate policy and an unfaithfulness to the brotherhood which, in spite of separation and corruption, still bound the two kingdoms in the covenant of God with Abraham, deserved and received prophetic rebuke. (See 2 Chronicles 16:7–9.) In the same way, Isaiah, in the days of Ahaz and Hezekiah, denounced the vain trust in alliances with the neighboring nations and alliance with Egypt (Isaiah 30:1–17).