The problem of evil as constructed here is based on a construct of God that is just one of many. Consider the following:
If we accept the good from God must we not also accept the evil? (Job 2:10)
I form the light, and create darkness: I make peace, and create evil: I the LORD do all these things. (Isaiah 45:7)
And the LORD repented of the evil which he thought to do to his people. (Exodus 32:14)
If both good and evil come from God then the concept of God’s benevolence as well as the concepts of good and evil need to be reexamined (unless, of course, one simply ignores all this and goes with a different version of things). God’s benevolence does not mean that God only does what is good. One might hope to reconcile this with cherished beliefs by assuming God’s benevolence is reserved for the righteous and malevolence for the wicked, but texts such as Ecclesiastes and Job, as well as experience tell us otherwise.
Perhaps part of the problem is the assumption that God is reasonable or can be understood by reason. That is the influence of Greek and later Enlightenment philosophy that overshadows the Jewish God who is characterized not by reason but by will. A God who, it is said, it is wise to fear, is transformed into a God who must be reconciled with reason.
If one is to understand the quotes above, good and evil cannot be reified. Good and evil have no moral agency. They refer to actions, intentions, and consequences that are beneficial or harmful. The history of the term ‘evil’ makes it difficult to see behind its more recent connotations. Alternative translations of the Hebrew are bad, adversity, calamity, destruction, misery, affliction. Evil, as it is understood in these passages, is not the work of the Devil or Satan.
A couple of more quick points:
Good and evil are fruits of the same tree.
Opposites in Genesis are often part of the same: the two creation stories the first a watery out of flux and the second a dry beginning where everything is in stasis until the rains, separating the light and dark and the ground from the water, male and female, man is the dust of the earth and the breath of God, life and death, both blessings and curses and pleasure and pain tied to procreation (literally knowledge) and childbirth (the opposition between Cain and Abel) as well as the painful toiling of the cursed ground that yields food.
But are you equally aware that the Euthyphro Problem is premised on polytheism, not monotheism?
The dialogue Euthyphro is premised on the assumption of knowledge of things not known, ignorance mistaking itself for wisdom. This is a problem that holds for monotheism as well as polytheism. The conflict between the gods is only one of the problems raised in the dialogue. The central problems are piety and justice and they pertain to a single God as well as multiple gods.
Present day "Euthyphros" love to visit sites like this to parade their “wisdom”, mistaking opinion for knowledge.
In my opinion, the real problem of evil is not the question of why there is evil, but the fact that there is evil, that we both inflict and are afflicted by evil. It is not something that can be eliminated but can be mediated. We would do better to stop looking to God and look to ourselves.