Ecclesiastes 1:13 And I set my heart to seek and search out by wisdom concerning all that is done under heaven; this burdensome task God has given to the sons of man, by which they may be exercised. [14] I have seen all the works that are done under the sun; and indeed, all is vanity and grasping for the wind.
The preacher sets out to determine whether what is done under Heaven has purpose of itself. In his own words, he set his heart to diligently seek out an answer; the compound descriptor emphasizing the sobriety and gravity of the seeker’s intention and effort. More than that, the preacher sought these things by wisdom.