Talmud
The term is discussed in the Babylonian Talmud, Makkot 23b and elsewhere. Rabbinical use is discussed by Joseph Jacobs and Ludwig Blau in the article "Holy Spirit" in the Jewish Encyclopedia of 1911.
In Judaism, God is One, the idea of God as a duality or trinity among may be considered shituf (or "not purely monotheistic"). The term Ruach HaKodesh (Holy Spirit) is found frequently in Talmudic and Midrashic literature. In some cases it signifies prophetic inspiration, while in others it is used as a hypostatization or a metonym for God. The rabbinical understanding of the "Holy Spirit" has a certain degree of personification, but it remains, "a quality belonging to God, one of his attributes".
In Rabbinic Judaism, the references to The Spirit of God, the Holy Spirit of YHVH, abound, however apart from Kabbalistic mysticism it has rejected any idea of The Eternal God as being either dualistic, tri-personal, or ontologically complex.
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