Albert Barnes Commentary Ecclesiastes 1:16

"I communed with mine own hear, saying, Lo, I have gotten me great wisdom above all that were before me in Jerusalem; yea, my heart hath had great experience of wisdom and knowledge." — Ecclesiastes 1:16 (ASV)

I am come ... - Rather, I have accumulated (literally “enlarged and added”) wisdom more than et cetera.

They that have been ... - The reference is probably to the line of Canaanite kings who lived in Jerusalem before David took it, such as Melchizedek (Genesis 14:18), Adonizedek (Joshua 10:1), and Araunah (2 Samuel 24:23); or, it may be, to Solomon’s contemporaries of his own country (1 Kings 4:31) and of other countries who visited him (1 Kings 4:34); (1 Kings 10:24). For “in” Jerusalem, render 'over'.