"And Aaron shall bear the names of the Children of Israel on the Breastplate of Judgment upon his heart, when he goes into the holy place, for a memorial before G‑d continually. And you shall put in the Breastplate of Judgment the Urim and the Thummim; and they shall be upon Aaron's heart, when he goes in before G‑d…." (Ex. 28:29-30)

It is known that the Breastplate barely contained all twenty-two letters of the Hebrew alphabet, as our sages have said.

There were twelve precious stones set in the Breastplate of Judgment. They were engraved with the names of the Patriarchs, Abraham, Isaac and Jacob, the names of the twelve tribes, and the words "tribes of Yeshurun". Certain letters, such as the gimel or the zayin, were written only once.(Yoma 73b)

The Breastplate of Judgment was a prophetic device, worn by the High Priest….

The Breastplate of Judgment was a prophetic device, worn by the High Priest, through which questions could be asked of G‑d. When the king or the High Court [i.e. Sanhedrin] would ask a question, the priest would see various letters sparkle or bulge out. Using Divine Inspiration, he would then be able to combine the letters to spell out the answer.

Therefore, when they had to ask a question that used several of the same letters, such as "Should I go to Bavel", how were they answered?

The question "Should I go to Bavel?" contains two letters beit, and three lameds. However, it is likely that the author was only using this as an example of a phrase with repeating letters, because there were at least five beits and four lameds in the Breastplate - enough to spell out these words.

There is a very great mystery in this . . . I heard from my grandfather [the Baal Shem Tov], that each of the twenty-two letters [of the Hebrew alphabet] contains within it all the other letters of the alphabet (except for the letter mem).

The engraved letters shone in their expanded forms….

These can be attained by spelling out each letter in full. For instance, writing out the letter alef in full provides a lamed and a pei. Furthermore, each of these letters can be further expanded, to produce even more letters, until the entire Hebrew alphabet is reconstituted. The exception to this phenomena is the letter mem, which when written in full will not produce any additional letters. [Original editor's note]

Since G‑d commanded that all twenty-two letters be inscribed on the Breastplate, when the priest would be enwrapped in Divine Inspiration, the letters would shine in their expanded forms. This enabled them to receive everything they needed to know. Understand this!

This is the meaning of "onyx stones and stones to be set [in Hebrew, 'Avnei miluyim'], for the ephod, and for the breastplate". (Ex. 25:7)

"Avnei miluyim", can be read alternatively as "stones that are filled out" - meaning that the engraved letters shone in their expanded forms.

In a number of other lessons on this theme, the Baal Shem Tov explains that additional letters can be derived from a single letter by using the techniques of gematria, or by dividing the letters into their component parts. It is possible that those approaches were originally mentioned with this lesson, since there are a number of other letters, such as the gimel, zayin, chet, tet and samech that could never be derived from the other letters, no matter how many times they are spelled out. [See Baal Shem Tov on the Torah, parashat Yitro, fn. 11, for more on this subject.]

[Adapted by Eliezer Shore from Degel Machane Ephraim, Likutim.]