The roof of the Mishkan was made of multiple layers of coverings that created a canopy over the Mishkan and draped over the outside of the walls. Each layer was made from different materials.
The bottom covering was woven from thread that was spun with white linen and three types of dyed sheep wool; blue, crimson and purple. Above this, a second covering was draped, made from spun goats’ hair.
These two coverings, one of sheep-wool and the other of goat-hair, represent the service of the righteous Tzaddik and the Baal Teshuvah respectively.
Sheep are docile and obedient animals and their wool is soft and white. This represents the purity of the Tzaddikim, who faithfully and effortlessly follow Hashem’s will, never struggling with temptation or having to overcome the ‘wildness’ of a Yetzer Hara.
In contrast to the gentle sheep, goats are wild and rowdy. Unlike the sheep’s soft, white wool, the goat’s hair is coarse and black. This represents the Baal Teshuvah who must constantly struggle to overcome their state of spiritual darkness and the agitation and coarseness of their Yetzer Hara, to be able to serve Hashem.
The sages debated which type of service is greater, because each has its own quality. The Tzaddik’s Avodah is flawless, but it comes naturally and without effort. The Baal Teshuvah may not have the same perfection, but their spiritual accomplishments come with great effort and self-transformation.
The 2 coverings remind us that both have their unique place and part in the service of building Hashem’s home.