“Consider the work of God!
Who can make straight
What he has made crooked?
In the day of prosperity
In the day of adversity
God has made the one
As well as the other.
Thus mortals may not find out anything
That will come after them.”
Qoheleth wants us to look at the work of God. Can anyone make a crooked way straight? Remember that God has made both the days of prosperity and the days of adversity. Mortals would like to know about the future, but only God knows what will come after the life of a mortal.
“See, I have set before you this day life and prosperity, death and adversity. If you obey the commandments of Yahweh your God that I am commanding you today, by loving Yahweh your God, by walking in his ways, and observing his commandments, decrees, and ordinances, then you shall live and become numerous. Yahweh your God will bless you in the land that you are entering to possess. But if your heart turns away and you will not hear, but are led astray to bow down to other gods and serve them, I declare to you today, that you shall perish. You shall not live long in the land that you are crossing the Jordan to enter and possess. I call heaven and earth to witness against you today, that I have set before you life and death, blessings and curses. Choose life so that you and your descendants may live, loving Yahweh your God, obeying him, and holding fast to him. For that means life to you and length of days, so that you may live in the land that Yahweh swore to give to your ancestors, to Abraham, to Isaac, and to Jacob.”
This idea of the two ways, one of death and one of life, is very common among many religions. The early Christian teachings of the Didache used this concept, as did many other dualistic religions that point to the choice of life or death, good or bad, the basic choices in life. Yahweh is giving you the choice, life and prosperity or death and adversity. You choose your path. You get either the blessings or the curses.