Brief Synopsis
א Question one: What is the inner significance of the Eiphod and the Choshen?
Question two: Why on the Choshen was there twelve individual stones all of different types and colours, yet on the Eiphod there were only two and they were the same?
Question three: Why was there a need for both the remembrance on the Eiphod and again on the Choshen?
בּ The Eiphod, Aharon wore from behind - ‘Achorayim’. The Eiphod is a half-hearted ‘Avodah’ of ‘Ochor’ which is only ‘Iss-kafya’. The Choshen Aharon wore in front -‘Ponim’. The Choshen is Avodah of ‘Iss-hapcha’. Transforming Middos from the animal soul to be like the Divine soul. This type of Avoda is called ‘Ponim’.
Aharon carrying the names of the B’nei Yisroel on both the Eiphod and on the Choshen is in order to empower the B’nei Yisroel to engage in the two types of Avodah of ‘Iss-kafya’ and ‘Iss-hapcha’.
Not only for an Avodah of Achorayim and ‘Iss-kafia’ does one need the empowerment from Aharon. But even with the Avodah of Ponim and ‘Iss-hapcha’ one also needs the empowerment from Aharon. But that empowerment can raise them up way above the Name of Hashem.
ג Since the Choshen is Avodah of ‘Iss-hapcha’ - refinement of all the different colours and styles of the different animal souls and incorporating all these colours and styles into the Divine soul. So that, each refined soul is a different colour and style.
Therefore, there are twelve stones corresponding to twelve Shevotim which corresponds to the twelve edges of a three-dimensional object, and the twelve different gates for the twelve unique prayers each from a different one of the twelve Shevotim. Each ascends through its own unique gate.
In the desert, the twelve Shevotim were divided into four camps and each camp has three Shevotim. So too, the Choshen has four rows and each row has three stones.
But the Eiphod, worn on Aharon’s back, which is a state of ‘Ochor’, only empowers the yet unrefined animal soul to work on its ‘Iss-kafya’ which is equal for all Shevotim on same Shoham stone.
Shoham are the same letters as Moshe. Moshe empowers ‘Iss-kafya’. The Shoham stone in the Choshen is Yosef’s stone. Yosef represents ‘Yichudoh Ilo’oh of Atzilus. Another koach for the Avodah of ‘Iss-kafya’.
ד When B’nei Yisroel left Egypt, it was still only an Avodah in ‘Iss-kafya’ of Achorayim. Waging war against Amalek requires Moshe’s men. Impetus for Avodah in ‘Iss-kafya’ needs to be drawn from a very high place.
ה In order to extract the B’nei Yisroel from Mitzrayim or to extract the Divine soul from limitation and boundaries, empowerment from Aharon’s elevation suffices. To elevate the animal soul however, can only be done with an empowerment in the form of a Hamshocho through Moshe. Because only Moshe, can break down the coarseness and vulgarity of Pharoh. Thereafter, Aharon can elevate. For the Avodah of ‘Iss-kafya’ (Represented by the Eiphod with the Shoam stones) one needs the unique impetus and empowerment offered by the Shoham from Moshe Rabeinu. Shoham-Moshe same letters.