"By the spirit of inspiration the king recorded for after generations the history of his wasted years with their lessons of warning. And thus, although the seed of his sowing was reaped by his people in harvests of evil, his life-work was not wholly lost. With meekness and lowliness Solomon in his later years “taught the people knowledge; yea, he gave good heed, and sought out, and set in order many proverbs.” He “sought to find out acceptable words: and that which was written was upright, even words of truth.” “The words of the wise are as goads, and as nails fastened by the masters of assemblies, which are given from one shepherd. And further, by these, my son, be admonished.” Ecclesiastes 12:9-12 . PK 79.1"
"And moreover, because the preacher was wise, he still taught the people knowledge; yea, he gave good heed, and sought out, and set in order many proverbs. The preacher sought to find out acceptable words: and that which was written was upright, even words of truth. The words of the wise are as goads, and as nails fastened by the masters of assemblies, which are given from one shepherd. And further, by these, my son, be admonished: of making many books there is no end; and much study is a weariness of the flesh."
Ellen White directly references Ecclesiastes 12:9-12 in this passage.