There are two different kinds of darkness in the world. The first one which comes to mind is physical darkness, when someone, G-d forbid, does not have the gift of sight. It's a terrible thing and, in fact, every morning in the blessings of ברכת השחר (Birkhoth HaShahar), we thank הקדוש ברוך הוא (HaQadosh Barukh Hu), for opening our eyes and giving us the ability to be able to see.
There is , however, another level of blindness, which is spiritual. Spiritual blindness is as difficult and as painful as physical blindness; in fact, in a sense, it is even worse and many are unaware that they are imprisoned in this dark lack of spirituality. Perhaps their נשמה (Neshamah/soul) cries out and says, "Set me free, get me out to the light!"
The month of Elul (אלול) is a special time when we are able to give our holy Neshamah more of a chance to sense the spiritual light. How do we do it? First of all, we're told that the month of Elul is an acronym for the phrase "Ani Ledodi Wedodi Li" (אני לדודי ודודי לי/I am for my beloved and my beloved is for me), as written in Shir HaShirim (שיר השירים). Shir HaShirim is all about the unique and intimate relationship between הקדוש ברוך הוא, the Holy One blessed be He, and the Jewish people, which is likened to the intimate relationship between a husband and his wife.
How can one reach such a level? How is it possible for us to sense this amazing light that emanates from the Holy One blessed be He? Only when I am able to make my "I", my "אני", as small as possible, can I reach the level of "Ani Ledodi Wedodi Li" and the intimate relationship with HaQadosh Barukh Hu. Once I am able to reach this level, I am surrounded by this light.