The truth is this: The radiation of light is Godly. In what way? Godliness is hidden from the created realms and their inhabitants, but they must nevertheless receive some revelation of it at the time when it is revealed to them. A comparable case is that of the beams of light that radiated from the face of Moses our Teacher, peace be upon him.
Someone who stood before Moses would be ashamed to look directly in his face and would lower his eyes – and then he would see Moses’ radiance. Godliness is revealed to His creatures in the same way, yet they do not see it directly. What they see is only the radiance shining from Him, and this radiance is the Sefirot. This radiance relates to its Owner, being the revelation of the splendor of the glorious essence that remains concealed.
That which is revealed of Him – this radiation of light, the Sefirot – is the radiance of Eyn Sof, blessed be He, namely the revelation of His splendor. If so, the Sefirot are bound up with Eyn Sof, blessed be He, the Owner and Source of this radiation.