What is the virtue of reciting Surat Al-Kahf on Friday, and what is meant by "a pillar of light" in the context of its virtue?

Several hadiths have been narrated regarding the virtue of reciting Surat Al-Kahf on Friday, among them: "Whoever recites Surat Al-Kahf on Friday, a light will illuminate for him between the two Fridays," and "Whoever recites Surat Al-Kahf on Friday, a light will illuminate for him between him and the Ancient House (Kaaba)," and "Whoever recites Surat Al-Kahf on Friday, a light will shine for him from beneath his feet to the clouds of the sky, illuminating for him on the Day of Resurrection, and his sins between the two Fridays will be forgiven." The mentioned light may be spiritual (guidance and protection from sins) or physical (a light shining from beneath the feet and appearing on the face on the Day of Resurrection and in this world). This virtue is attained by whoever recites the Surah on Friday or its eve.