We often think that if we could perform a miracle for somebody they would certainly believe in Jesus Christ. We have friends or family or coworkers who seem skeptical. And we think, If I could only perform one miracle, I know they would believe. But to be honest with you, I'm not so sure they would. Judas Iscariot, who betrayed Jesus Christ, witnessed many miracles. He saw Jesus heal the blind, deaf, and lame. Before his very eyes, Christ dramatically healed lepers and even raised a man named Lazarus from the dead. Judas stood in the presence of Jesus as He calmed angry storms and defied natural law by walking on water. But still he did not believe. In the end, this supposed friend and follower of Christ, who witnessed miracle after miracle, turned out to be a fraud and betrayed the Lord.
People do not necessarily need to see a miracle in order to believe in Christ. Jesus provided us the real reason why people do not believe when He proclaimed,
"And this is the condemnation, that the light has come into the world, and men loved darkness rather than light, because their deeds were evil. For everyone practicing evil hates the light and does not come to the light, lest his deeds should be exposed." (John 3:19)
A person can say, "I don't believe, because I'm not convinced." But in reality, the core reason why most people reject the Lord is that they love darkness rather than the light of God.