What does John 1:5 mean?

Jesus' light came to the world during a dark time. Sadly, mankind didn't respond very well. The second phrase of this verse is sometimes translated as "the darkness did not overcome it," or "the darkness did not comprehend it." The original Greek root word is katalambanō, which can mean "acquire," "grasp," or "lay hold of." Since light is associated with knowledge, this means that Jesus was not—is not—understood by the world-at-large. Many people who reject the gospel do so because they misunderstand it. This inability to see Jesus for what He truly is has more to do with a person's stubbornness than with their intellect (John 7:17). The evidence is there, but those who prefer darkness will not see it for what it is.

The Greek wording also carries a sense of "seizing," as in taking possession. Of course, the world would physically "grasp" the person of Jesus (John 19:18), but it could not overcome the Messiah (John 19:19–20; 1 Corinthians 15:3–5).