"Blessed be the LORD your God, who has delighted in you and set you on his throne as king for the LORD your God! Because your God loved Israel and would establish them forever, he has made you king over them, that you may execute justice and righteousness."
2 Chronicles 9:8
This blessing from the queen of Sheba speaks for the many gentiles who came to Jerusalem by the lure of Solomon's fame and the draw of the wondrous temple of Yahweh. She is drawn to make a statement of worship of God. That was exactly what the temple worship was meant to inspire among the nations. And to this pagan queen, it was clear that the blessing of God was upon Solomon and his kingdom. It was in this way that Israel was to bless all nations.
There are several observations that the queen of Sheba made that are insightful. You can see them in the blessing she proclaims to Solomon. The first is the sheer grace of God. Solomon and Israel enjoyed this time of prosperity because God delighted in them. The queen saw the unmerited favor of the Lord showered upon Israel and she blessed God for His grace. She also acknowledged the awesome stewardship Solomon administered in Jerusalem. The king was ruling "for the LORD". God was the true king of Israel and Solomon was His servant. It took a pagan woman to praise God for this truth.
She marvels at the love of God displayed in the covenant. Somewhere in her journey in Jerusalem, with all the questions she gave to Solomon, she realized the unique covenantal relationship Israel had as Yahweh's people. She saw the current prosperity as the blessing of this covenant. The questions she had for Solomon must have been deeply spiritual. I am inclined to think the queen of Sheba converted and became a gentile proselyte follower of Yahweh as a result of this encounter.
Finally, she blessed God for the way in which Solomon fulfilled the Davidic covenant. She saw how God filled Solomon with wisdom so that as king, Solomon might execute God's justice and righteousness in his rule over Israel. She connected all the dots of the covenant and God's sovereignty. She understood God and His dealings with His people. She worshiped the Lord.