And they came from all nations to hear the wisdom of Solomon, and from all the kings of the earth, who heard of his wisdom.

People came from every nation to give ear to the wisdom of Solomon, from all the kings of the earth who had word of his wisdom.

And they came from all the peoples in order to hear the wisdom of Solomon, and from all the kings of the earth, who were hearing about his wisdom.

There came of all people to hear the wisdom of Solomon - We learn from 1 Kings 10, that the queen of Sheba was one of those visitants, and perhaps the most remarkable, as we have the particulars of her visit, but not of the others.
It is astonishing that of a person so renowned for wisdom, so little should be left to prove the truth of a fact of which all the civilized nations of the world have heard, and of which scarcely any man has ever doubted. The people that came from all kings of the earth were probably ambassadors, who came to form and maintain friendship between their sovereigns and the Israelitish king. We cannot understand the place as speaking of people who, either through an idle or laudable curiosity, came to see and converse with Solomon; to give free access to such people would ill comport with the maintenance of his dignity.

And there came of all people to hear the wisdom of Solomon,
from all kings of the earth,.... Who sent their ambassadors to his court to know the truth of what was reported, and bring them some proofs and specimens, by which they might judge of the truth of the relations that had been told them; which perhaps might seem to them to be beyond all belief:
which had heard of his wisdom; for the fame of it was spread everywhere by merchants and travellers, and such sort of persons, who had been at Jerusalem, and were masters of various anecdotes relating to Solomon; which they industriously spread in the several parts of the world they had dealings in.

The widespread fame of his wisdom brought many strangers to Jerusalem, and all the more because of its rarity at that time, especially among princes. The coming of the queen of Sheba to Jerusalem (1 Kings 10) furnishes a historical proof of this.
(Note: Greatly as the fame of Solomon's wisdom is extolled in these verses, it was far outdone in subsequent times. Even Josephus has considerably adorned the biblical accounts in his Antiqq. viii. 2, 5. He makes Solomon the author not only of 1005 βιβλία περὶ ᾠδῶν καὶ μελῶν, and 300 βίβλους παραβολῶν καὶ εἰκόνων, but also of magical books with marvellous contents. Compare the extracts from Eupolemus in Eusebii praep. Ev. ix. 31ff., the remnants of Solomon's apocryphal writings in Fabricii Cod. apocr. V. T. i. pp. 914ff. and 1014f., the collection of the Talmudical Sagas in Othonis Lex. rabb. philol. pp. 668f., and G. Weil, bibl. Legenden der Mussulmnner, pp. 225-279. According to the Koran (Sure xxvii. 1-Kings 4:17.), Solomon understood the languages not only of men and demons, but also of birds and ants. The Turkish literature contains a "Book of Solomon," Suleimanname, consisting of seventy volumes, from which v. Hammer (Rosenl, i. p. 147ff.) has given extracts.)

All kings - All the neighbouring kings; a restriction grounded upon the following words, where this is limited to such as heard of Solomon's wisdom. Let those who magnify the modern learning above that of the ancients, produce such a treasury of learning, anywhere in these later ages, as that was, which Solomon was master of. Yet this puts an honour upon human learning, that Solomon is praised for it, and recommends it to the great ones of the earth, as well worthy their diligent search. In all this Solomon was a type of Christ, in whom are hid all the treasures of wisdom and knowledge.