14 And he made curtains of goats’ hair for the tent over the tabernacle: eleven curtains he made them.
15 The length of one curtain was thirty cubits, and four cubits was the breadth of one curtain: the eleven curtains were of one size.
16 And he coupled five curtains by themselves, and six curtains by themselves.
17 And he made fifty loops upon the uttermost edge of the curtain in the coupling, and fifty loops made he upon the edge of the curtain which coupleth the second.
18 And he made fifty taches of brass to couple the tent together, that it might be one.
19 And he made a covering for the tent of rams’ skins dyed red, and a covering of badgers’ skins above that.
The previous post detailed Bezaleel’s creation of the linen covering, which was the innermost layer, the one that was visible from the interior. Today we hear about all the following layers: the ones of goats’ hair, rams’ skin, and badgers’ skin. These would be visible from the outside, and I would imagine that they effectively blocked out the sun, such that the only illumination would be from the seven lamps on the menorah.
Of course, the menorah was only on one side of the inner curtain, which means there would have been no direct light source for the most holy place, only whatever light leaked in. We do not know how thick the inner curtain was, so maybe light was able to pass through or maybe not. If the most holy place was quite dim, this might seem like a strange choice given the common connection between God and light; but there are a couple possible reasons why this feature could have been fitting.
One explanation could be that this would help the priest to disconnect from the material world. Cutting off his sight may have helped him to surrender his own perception and reason, encouraging him to listen to his spiritual senses instead. Another reason might have been to symbolize the great shroud of mystery that still surrounds God, even when we are at our closest to Him. His depth and breadth are simply unfathomable and imperceivable to us. A third possibility is that the room might have been illuminated, but not by a natural light source. If Moses’s face was made to shine from his visits into the tabernacle, perhaps there was a divine glow that originated in there.

