2 Samuel 8:6
Then David put garrisons in Syria of Damascus: and the Syrians became servants to David, and brought gifts. And the LORD preserved David whithersoever he went. Then David put garrisons in Syria of Damascus: and the Syrians became servants to David, and brought gifts. And the LORD preserved David whithersoever he went.
The verse belongs to the account of David's triumph as God's chosen ruler after the long conflict between Israel and Judah, when he became the beloved king over all the tribes of Israel and his enemies were subdued. His victories greatly enlarged Israel's borders and increased its dominion, and after he became king over all Israel his enemies were subdued. In this campaign David defeated the Syrians of Damascus, killing 22,000 men.
He then put garrisons in Syria of Damascus at Damascus, extending his kingdom into Syria and eastward to the Euphrates. By those garrisons he brought the Syrians under his rule, so that they became his servants and subjects who brought gifts and paid tribute. The Lord preserved David whithersoever he went, showing divine providence in building up his kingdom.
These victories brought the broadest expansion of Israel's kingdom under David, greatly enlarging its borders and increasing its dominion tenfold to an extent never reached by his successors. This security gave David rest from his surrounding enemies, and in that rest he turned his thoughts to building a permanent house for God. He did so because he himself dwelt in a house of cedar while the ark remained in a tent he had pitched for it, with the tabernacle itself still at Gibeon.
These victories and prosperity marked the height of David's power, when ease and wealth may have blinded him and hardened his heart before his fall. Damascus later passed from Israel's control near the end of Solomon's reign. The verse is also part of the record of Israel's later history showing that practices forbidden by God were nevertheless carried out and the prohibition was not always obeyed. David's military action against Syria of Damascus was a just war, so he was not a murderer for fighting in a just cause.