The Bible’s answer
The Bible shows that God did not create the Devil. Instead, He created the person who became the Devil. Regarding God, the Bible says: “Perfect is his activity, for all his ways are justice. A God of faithfulness, with whom there is no injustice; righteous and upright is he.” (Deuteronomy 32:3-5) From that statement, we can conclude that Satan the Devil was at one time perfect and righteous, namely, one of God’s angelic sons.
At John 8:44, Jesus said that the Devil “did not stand fast in the truth,” implying that Satan had at one time been truthful and guiltless.
However, like the rest of Jehovah’s intelligent creatures, the angel who became Satan had the freedom to choose between right and wrong. By choosing a course in opposition to God and inciting the first human couple to join him, he made himself Satan, which means “Resister.”—Genesis 3:1-5; Revelation 12:9.