I was asked this question anonymously by someone I assumed was an atheist or agnostic, given its inference. But it is a thought-provoking and complex inquiry nonetheless.
Perhaps the person who asked this question was not an atheist but a young adult who was trying to ascertain whether things like lying, cheating, or stealing would still be considered wrong if God did not exist. In other words, if there were no God (hence, no standard of morality), would those acts or behaviors be acceptable?
Or maybe this individual was asking because they believe God is responsible for bringing evil into existence. Therefore, given their assumption, they want to know if the world and its inhabitants would be better off without God.
Obviously, there could be numerous reasons why people would pose this question. Regardless, the answer is simple and very straightforward: Nothing would exist if God did not exist. However, that fact does not mean or imply that Jesus created evil.
The Bible says that everything God created was good and very good (see Genesis 1:25, 31). It also states that Jesus created everything in existence. Colossians 1:16 says, "For by Him all things were created, both in the heavens and on earth, visible and invisible, whether thrones or dominions or rulers or authorities-all things have been created through Him and for Him."
However, despite Jesus creating all things, evil is not created matter like mountain ranges, stars, or the sun. It is the absence of righteousness, much like darkness is the absence of light.
Furthermore, God is righteous. It says in 1 John 1:5, “God is Light, and in Him there is no darkness at all.” Revelation 4:8 says, “Holy, holy, holy is the Lord God, the Almighty, who was and who is and who is to come.” It also says in Deuteronomy 32:4, “His work is perfect, for all His ways are just; a God of faithfulness and without injustice, righteous and upright is He.” Therefore, God cannot exhibit evil, nor is He the source of any unrighteousness.
The reason evil exists in the world is that people willfully choose unrighteousness over holiness to appease their fleshly cravings. This trend began with Adam and Eve in the perfect world God created and has perpetuated through every generation since.
Norman Geisler wrote an interesting article entitled “If God Exists, Why Is There Evil?” I think you will find it informative regarding this question and subject matter.