The following resources linked below are by Jewish scholars Daniel Boyarin and Alan F. Segal. Neither believe Jesus is the Jewish Messiah. Nevertheless they documents the fact that there were many (not all) Jews before, during and after the time of Jesus who believed in at least two persons who were Divine according to the Hebrew Scriptures.
The Gospel of the Memra: Jewish Binitarianism and the Prologue to John
by Daniel Boyarin
[or
HERE]
TWO POWERS IN HEAVEN Early Rabbinic Reports about Christianity and Gnosticism by Alan F. Segal
[I recommend the
PDF version]
See also the following resources by Jewish believers in Jesus as Messiah
Christian William Henry Pauli's classic book,
The Great Mystery; or, How Can Three Be One?
Arnold Fruchtenbaum's
The Jewish Life of Christ; Twenty One (21) mp3 Lectures
Michael L. Brown's
Answering Your Toughest Questions; (32 videos) introductory lectures