John Gill Commentary 1 Kings 4:29

"And God gave Solomon wisdom and understanding exceeding much, and largeness of heart, even as the sand that is on the sea-shore." — 1 Kings 4:29 (ASV)

And God gave Solomon wisdom and understanding exceeding much ,
&c.] In things natural, moral, divine, and spiritual, and that not slight and superficial, but exceeding deep, and large beyond expression; and this he had not from the acuteness of his genius merely, nor from his industry and diligence; but by the gift of God, as whatsoever solid wisdom and understanding is in any man, it is from the liberal hand of God, the fountain of wisdom, (James 1:5);

and largeness of heart, even as sand that [is] on the seashore ;
he had a genius and capacity to receive anything; his knowledge was vast and comprehensive; it reached to and included things innumerable, as the sand of the sea; there was scarce anything under the heavens, or on the earth, and in the sea, but came within the compass of it, as what are later mentioned show.