The book Ecclesiastes is a book of Wisdom, and consists in a set of reflections and poems about the nature of human life written by the wise Kohelet: Vanity, pure Vanity!, reflects the wise in Ecclesiastes 1: 1.
The teacher, a devotee of wisdom reflects: "I  applied my mind to study and to explore by wisdom all that is done under the heavens" Ecclesiastes 1:13, "I accumulate great wisdom, more than all my predecessors", Ecclesiastes 1:16, to conclude "For with much wisdom comes much sorrow: the more knowledge, the more grief", Ecclesiastes 1:18.
These reflections of the wise although they are tinged with a certain pessimism what they seek is to give us the idea that even if studying the Bible, knowing famous quotes, beautiful and encouraging, inspirational phrases, gives us a certain security, a certain vanity, "wisdom is no guarantee of anything", since in everything intervenes time and chance.
Among its most important teachings distinguish, the famous saying:
Wisdom is better than strenght. Ecclesiastes 9:16
The translation of wisdom in the old testament can be interpreted as intelligence, ingenuity, dexterity. Kohelet explains that there is a wisdom related to experience, "with the know-how", example: the architect built with wisdom.
We can all be wise in some profession, wisdom is not only a spiritual gift, we can be wise also in some activity where we can demonstrate our skill.
Dexterity is the opposite of cunning, wisdom is the opposite of ignorance, reason is the opposite of passion. To this refers the refrain, not to act with passion or ignorance but seeking to act with dexterity, with intelligent wisdom.