Ecclesiastes 2:20-22

Therefore I turned my heart and despaired of all the labor in which I had toiled under the sun. For there is a man whose labor is with wisdom, knowledge, and skill; yet he must leave his heritage to a man who has not labored for it. This also is vanity and a great evil. For what has man for all his labor, and for the striving of his heart with which he has toiled under the sun?