With the lighting of the fourth candle, light and darkness are now evenly divided. Until now we were overwhelmed in darkness, but with each night's added candle the light has grown. And tonight, with the lighting of the fifth candle, the light will have outgrown the darkness and it will only grow brighter and brighter until eight candles - the number above nature.
May we all merit to witness the final defeat of darkness by the light that will never diminish or go out.
You shall no longer have the sun for light by day, and for brightness, the moon shall not give you light, but the Lord shall be to you for an everlasting light, and your God for your glory. Your sun shall no longer set, neither shall your moon be gathered in, for the Lord shall be to you for an everlasting light, and the days of your mourning shall be completed. (Yeshayahu 60.19-20)