Jesus is the
perfect Light referred to in this verse. The star led the wise men to Jesus. Jesus proclaimed later on in his life "I am the light of the world"
http://biblehub.com/john/8-12.htmJesus came to shine His light on the darkness (wrong, evil, selfishness) in our hearts by Him living a perfect life of extreme selfless love and purity for us to follow so that we could find a way of living in relationship with our creator God.