"Is God willing to prevent evil, but not able?
Then he is not omnipotent.
Is he able but not willing?
Then he is malevolent."
The answer is:
A. He cannot do the impossible, or
B. Both A and C, or
C. He is not omnipotent.
For example He cannot cause history that has occured to have not occured.
He cannot make non historical the "disappearance" of my post {similar to
this one} that was immediately after yours in this thread.
Is God both able and willing?
Then whence cometh evil?
Evil, sin, demons, angels, all is from the benevolent Creator Who is Love
and works all things together for good that He may be the Saviour of all.
"I form the light, and create darkness: I make peace, and create evil: I the LORD do all these things."
"Who will have all men to be saved, and to come unto the knowledge of the truth."
"...to reconcile all to Him...whether on the earth, or in the heavens."
"And we have known and believed the love that God hath to us. God is love; and he that dwelleth in love dwelleth in God, and God in him."
Is He neither able or willing?
Then why call him God?
Epicurus 341 –271 BCE
He is willing. Ultimately sin and evil will be gone when they are no longer
of any use, and God will be "All in all" (1 Corinthians 15:28}.
"And every creature which is in heaven, and on the earth, and under the earth, and such as are in the sea, and all that are in them, heard I saying, Blessing, and honour, and glory, and power, be unto him that sitteth upon the throne, and unto the Lamb for ever and ever." {Revelation 5:13}.