Ecclesiastes 1:14

I have seen all the works that are done under the sun; and, behold, all is vanity and vexation of spirit.

Solomon's searching into all the works done under the sun is empty and worthless compared with the knowledge of true holiness that opens the gates of the city of God. Age after age the same futile search goes on, as human curiosity reaches for the tree of knowledge thinking it is plucking the fruit most essential, while human ambition reaches for the kind of knowledge that brings glory and self-exaltation and supremacy. That seeking ends as Solomon's did, finding nothing of lasting value. It was the same ambition that led Adam and Eve to break through God's restraint in order to gain the knowledge God had withheld from them and to learn by experience the result of transgression, thereby giving the sons of men a practical acquaintance with evil. In contrast to that pursuit, Christ has planted for humanity the tree of life, whose leaves are for the healing of the nations.