It is difficult, although not impossible, to have a real appreciation for some of the deeper studies of religious Judaism without a knowledge of Hebrew and, to an extent, Aramaic. Unlike Christianity, where the Greek texts of the New Testament are not subject to scrutiny, the Hebrew texts of the bible, on the level of language and even of alphabet, have been seen as a mine to excavate some of the deeper meanings and secrets of the Torah.
The Wisdom in the Hebrew Alphabet, by Rabbi Michael L. Munk, gives English reading audiences a chance to get the flavor of the language based mystical theology of the Torah through an examination of each letter of the Hebrew alphabet. Munk delves into gematria, the mystical names of God, the hidden and revealed Torah, the meat and bones of Judaism’s esoteric and arcane lore. He explains this concepts in a way that most can understand, taking apart the Hebrew and rendering it into clear English.
Unless you read Hebrew, and have knowledge of the games the rabbis would play with the language, this is the book that will get you closest to the text centered orientation of mystical Judaism.